US2494402A - Looper - Google Patents

Description

Jan. 10, 1950 W. H. MURSCH LOOPER Filed June 22, 1945 Jig. 1.

' l l y I 4 Sheets-Sheet l INVENTOR Will/am Ii Nurse/2 ATTOR Y Jan. 10, 1950 w. H. MURSCH 2,494,402

' LOOPER Filed June 22, 1945 4 Sheets-Sheet 2 Jig. J. M

INVENTOR \Iglliam H. Mum [/7 Jan. 10, 1950 w. H. MURSCH 2,494,402

LOOPER Filed Juhe 22, 1945 4 Sheets-Sheet a Jig. 4.

INVENTOR Lgm'am l1. numb Jan. 10, 1950 w. H. MURSCH 2,494,402

LOOPER Filed June 22, 1945 4 Sheets-Sheet 4 INVENTOR ATTIOR Y D Patented Jan. 10, 1950 LOOPER William H. Mursch, Grafton, Pa", aasignor to Carnegie-Illinois Steel Corporation, a corporation of New Jersey Application June 22, 1945, Serial No. 600,991

Claims. (01. 271-2.2) 4

This invention relates to an improved mechanical looper for allowing the controlled gathering of a localized excess of traveling elongated material, such as strip, and thus the temporary slowing or stopping of strip entering the looper while continuing the travel of forward portions on the exit side of the looper.

The invention has among its, objects the provision of an improved looper of the mechanical vision of a mechanical looper wherein the momentum and inertia effects of the movable loop creating head are reduced, whereby high stresses and strains in the elongated -material are avoided.

These and other objects of the invention will become more apparent in the following description of the preferred embodiment of the invention, which is illustrated in the accompanying drawings, in which:

Figure 1 is a diagrammatic view of the strip looper of the present invention and associated mechanism with which it maybe employed;

Figure 2 is a view in side elevation of the looper of the present invention;

Figure 3 is a view in end elevation of the looper shown in Figure 2, the view being taken from the left hand and of Figure 1, the stationary loop supporting rollers on the movable carriage being removed for the sake of clarity;

Figure 4 is a view in horizontal cross section through the looper shown in Figure 2, the section being taken along the line l4 in Figure 2;

Figure 5 is a view in plan of the looper shown in Figure 2;

Figure 6 is a diagrammatic view of the pneumatic cylinder for supporting the last idle roller on the movable head of the looper shown in Figures 2, 3, and 4, and the control mechanism associated therewith;

Figure 7 is a wiring diagram for the looper mechanism whereby raising and lowering of the movable looper head are automatically controlled; and

Figure 8 is an alternative wiring diagram for thelooper wherein lowering of the movable head of the looper is automatically controlled but the raising thereof is controlled manually.

Mechanical loopers of the type to which the present invention relates consist generally of one or more movable heads carrying loop-supporting idle rollers cooperating with idle rollers on an op posed head or heads whereby loops of the elongated material are formed-between the rolls on opposed heads while allowing travel of the material through the looper. Such loopers are employed for a variety of purposes, as for instance, in continuous strip processing lines such as lines for processing strip metal to provide enough excess strip at the entering end of the line so that the end of the coil being processed can be welded or stitched to the. end of a new coil without stopping the end of the strip being processed. Such looper may also be used at the other end of the line to allow stopping the strip while the welded or stitched portion is cut out n recoiling. The process to which the strip may e subjected may be electrotinning, pickling, continuous annealing, or other operations involving the con-' tinuous travel of the strip.

Mechanical loopers in use before the present invention, when used in high speed lines, give considerable trouble due to breaking the strip,

. if the strip is stopped too quickly at the location subject the strip to undesirably high tensions.

The,present invention overcomes such difliculties and makes possible the use of loopers of the Y mechanical type, as distinguished from those employing freely hanging loops, in lines where the strip travels at speeds materially inexcess of 400 feet per minute. Such object is accomplished by the looper of the present invention wherein movement of the movable head of the looper in a direction towards the base is initiated automatically by a relatively slight increase in strip tension, thus practically eliminating momentum and inertia. eiiects of the looper head and counterweight masses from the moving strip.

In Figure 1 there is shown a typical mode of use of the looper of the present invention. As there shown, metal strip 2 is fed from a coil 4,

in a suitable uncoiling device, led between'driven pinch rolls 5, through normally inoperative welding device 6, and the normally spaced jaws of a clamp mechanism 8 into the looper Ill. Feeding of the strip into the looper is accomplished by means of driven pinch rolls l2 and I4 and feeding of the strip out of the looper is controlled by driven pinch rolls [6 and I8. After leaving the latter rolls, the strip passes under guide roll 20 and through a drag bridle device indicated at under side of the carriage.

carried by carriage so at the exit end of the When the strip from one coil has been .ex-

, hausted, the trailing end of the preceding strip is stopped, as by stopping pinch rolls 1! and I4 and actuating clamp 8, so that the end is located at the welding machine 8 as shown. A further coil is then positioned in the uncoiler, its forward end is fed through pinch rolls 5, and such end welded to the trailing end of the preceding strip by welding means 8. During such time the forward end of the preceding strip continues to travel at the speed with which it is processed in the line. and it is to make this possible that looper ill with its vertically movable head or carriage 88 is inserted in the strip feeding line. As will be apparent, upon stoppage of the trailing end of the strip through the looper, the movable head ,38 thereof moves downward to shorten the loops and. to supply the strip necessary to allow continuation of feed of the forward end thereof. After the welding operation has been completed, strip from the new coil is again fed into the looper and the movable head 88 is again raised to be in readiness for a new operation involving stoppage of the trailing end of the strip there through.

The looper of th present invention is more fully shown in Figures 2 to 8, inclusive. As shown in Figures 2, 3, and 4, the looper consists of a vertical framework composed of four' vertical I-beams 24 and a horizontal top platform 28, securedthereto. Positioned on beams 24 are vertical track members 28 on which is guided a vertically movable head or carriage 38 having guide wheels 32 engaging the tracks. The carriage is provided, as shown in Figures 2 and 4, with spaced cable connecting means 84 and 88 to which are connected the hoist cables for the are then run overvthe idle sheaves 88 at the 4 pneumatic cylinder 12 attached to the carriage in avertical-"position. The piston in cylinder 12 is urged in an upward direction by means of pneumatic pressure acting within the cylinder against the bottom of the piston to which the piston rod is attached, such pneumatic pressure being admitted to the cylinder by means of the flexible hose I8 and conduit 14 connected to the cylinder. The upper end of cylinder 12 is vented to the atmosphere, as shown in Figure 6. Located on the opposing head, which in this instance is the foundation of the looper, in confronting relationship to the idle rollers 82 and 88 carried by the carriage, is a series of idle rollers 18 supported by means 80, said rollers being so spaced that rollers 82 and 68 may enter between them, and at the ends, between them and the sets of pinch rollers and I4 and I6 and I8, when the carriage is at its lowest position. When the carriage is in such position the looper may be easily threaded by running the strip through pinch rolls l2 and [4 over rollers 82- and 88 and under rollers 18 and thence through pinch rolls l6 and [8, following which the carriage may be raised to form the loops as shown.

As has been indicated, each of the pinch-roll sets consisting of rolls i2 and f4 and i8 and I8, respectively, is power driven. driving rolls i2 and i4 is shown in Figure 3, wherein such rolls are connected to a gear box 82 which is driven by a variable speed motor 7 84. A similar means is provided for driving pinch upper left hand corner of Figure 2, and thence downwardly to vertically movable counterweight 52. As shown in Figur 3, each pair of hoist cables is connected to their corresponding counterweight by means of a pivoted equalizer memshaft of which is in turn connected to worm reducer 58. Hoist drum 48 is connected to the slow speed shaft of reducer 88 and drum 48 is connected to the corresponding shaft of reducer 88.

The movable carriage 88 is provided with a series of loop carrying idle rollers 82, each of which is supported for rotation about a horizontal axis by bracket means 84 attached to the The idle roller 88,

lopper, is supported by bracket 88 affixed to the bottom end of piston rod in proiecting from rolls l8 and 18. Means is provided in the looper for limiting the extent of travel of the carriage 38 and for stopping the feeding means of the strip through the processing line should breakage of the strip occur. A limit switch" 88, shown in Figures 2 and 4, is provided for limiting the extent of travel of the carriage in an upward direction, said switch functioning to break the electric circuit to the hoist motor 84 upon contact with the switch by part of the carriage. A similar switch is provided at 88 for limiting the extent of travel of the carriage downwardly, said switch being located near the bottom of the looper in a position at the side thereof to be engaged by the carriage upon its being lowered to its lowest position, whereby th electric circuit feeding motor 54 is similarly broken.

.The means for stopping the feeding of the strip of the processing line upon breakage of the strip is shown in Figures 2, 4, and'fi. Limit switch 90, inserted in the main electrical feed circuit for the motors driving the conveying means for the strip through the line, including the motor 84 and the corresponding motor for driving pinch rolls l8 and i8, is located on the bottom of the movable carriage 38 as shown in Figure 2 and is at one side thereof as shown in Figure 4. A switch operating arm 92, supported for pivotal movement about a horizontal axis by supporting bracket 94, is provided with a transverse shaft.

98 and an outer transverst arm [00 lying below limit switch 90 for cooperation therewith. The outer end of arm 92 is forked, as shown in Figure 6, the forked arms 98 being positioned on opposite sides of piston rod 18. The parts are so proportioned and are so positioned with respect to each other that when roller 86 approaches its topmost position with respect to the carriage, forked ends 98 of arm 92 are contacted by supporting bracket 68 whereby the arm 92 is rotated counterclockwise, in Figure 2., and the switch operating arm "10 operates switch 98 to break the circuit thereto. The extent of travel of the arm The means for 02 in a clockwise direction is limited by meane of stop bolt I02 projecting through the arm. the am being normally maintained in its downward position by means of compression spring I04 positioned around the stop bolt.

The structure of the pneumatic cylinder means carrying roller 06 and the character of the mechanism associated therewith is more fully shown in Figure 6. In that figure there is shown an adjustable pressure regulating and manual shutoiI valve I08 connected in the air supplying line I6 for supplying air at a predetermined pressure to the space within cylinder I2 below piston I06. After passing through valve I00, the air is admitted to the cylinder when needed by valve II 0, which is shown as being of the type having a spring pressed plunger, external pressure on the plunger serving to open the valve From valve IIO the air enters the cylinder through pipe 14. A branch pipe II2 connected to pipe 14 is provided, such pipe being connected to an adjustable pressure relief valve II4, a pressure actuated rheostat M6 for varying the speed with which carriage 30 is raised, a pressure starting switch II! for hoist motor 54, and a pressure actuated rheostat I20 for varying the speed at which the carriage is lowered.

Bracket 66 carries on one side thereof a vertically traveling cam I22 for the purpose of actuating valve I I0. As shown, the cam has a relatively thin lower portion and a thicker upper portion connected by an inclined surface, such inclined surface being so located relative to the length of the cam that the pivoted valve operating lever I20 is operated to open valve IIO when the piston is at approximately the midpoint of its travel in the cylinder. The upper thicker portion of the cam serves to maintain the valve open, when the piston is at or below the midpoint of the cylinder, and the lower thinner portion of the cam allows the cam to remain closed when the piston is in its upper portion of its travel. Cam I22, which is guided for vertical travel by means of the back guiding rollers I24 and opposed side guide rolling rollers I26, further serves the function of preventing rotation of the" piston rod and thus maintaining the axis of roller 66 parallel to the axis of rollers 62.

In Figure 7 there is shown a wiring diagram for the operating mechanism of the looper by whiehtravel of the movable carriage in both the upward and downward directions may be automatically controlled. As there shown, hoist motor 54 is provided with an armature I30 and a shunt field I32, the motor being supplied with current from electric source L1 and L2. Speed control of the motor is accomplished by means of variable resistance in series with the armature,: the upper resistance I40 being employed when the carriage 30 is raised and the lower resistance I48 being employed when the carriage is lowered. Variable resistance I40 is actuated by air cylinder device I42 of pressure responsive rheostat II6, the air cylinder device comprising a cylinder and spring pressed piston so connected to the variable resistance that an increase in air pressure in the line II2 to which it is connected operates to increase the resistance and consequently to decrease the speed of motor 54. Vari able resistance I48, on the other hand, is operated by air cylinder I49 so that the resistance is decreased upon increase of pressure in line i I I2.

The shunt field I32 is connected to the source of electric current by means of a reversing switch I44 which is operated by air cylinder device III of pressure switch II3, as shown. The air cylinder device I36 may be in the nature of a corrugated expansible cylinder, such as a Sylphon control. and is connected to the reversing switch by means as that which operates reversing switch I44 from air cylinder I36 is a single pole double throw switch I34 which, in the position shown in Figure 7, completes the circuit from line In through line I46, limit switch 80, and variable resistance I46 to the armature of the motor. In the position which switch I34 assumes when the reversing switch connects the motor 54 for raising the head, the circuit from line L: to the armature is completed through switch I34, line I36, limit switch 86, and variable resistance I40.

The looper of the present invention, when employing the control circuit shown in Figure '7, functions in the following manner. It will be assumed for purposes of illustration that pressure regulating valve I00 is set at pounds per square inch, pressure relief valve H4 is set at pounds per square inch, and that the pressure starting switch II6 functions to start the hoist motor in a direction to lower carriage 30 when the pressure rises to 95 pounds per square inch and to raise the carriage when the pressure drops to 85 pounds per square inch. It will be understood, of course, that such pressures are 11- lustrative only and that different pressure values may be employed, depending upon the area of the piston I06, the tension which it is desired to maintain on the strip, and the pressure differences which it is desired will cause the various elements to operate.

When the strip has been threaded into the looper and carriage 30 has been raised by a circuit (not shown) manually controlling motor 54, such manual control circuit is then switched out and the control circuit shown in Figure 7 is made operative. Air is then turned into the cylinder I2 through the heretofore closed regulating valve I08, with the piston I06 in its lowermost position and thus the valve IIO held open by cam I22. The piston I06 will then rise until the cam closes the valve IIO. If the looper carriage," is in an intermediate position and thetension on the strip is not enough to overcome the air pressure, the air in cylinder I2 beneath piston I06 will expand and when this pressure decreases to 85 pounds per square inch, hoist motor 54 will be started in the hoisting direction by pressure switch H6. The carriage will continue' to rise, its speed being regulated by the pressure controlled rheostat II6, until the carriage reaches the top of its stroke, where the limit switch 06 shuts oil the current or until the tension on the strip becomes so high that the piston is pulled down and compresses the air in cylinder I2 above 85 pounds per square inch,

at which point the pressure switch II8 will stop the motor.

Under normal conditions, with the looper car- 7 fed rrom the uncoiler into the processing line, the

' pressure in the-cylinder will be between 85 and 95 pounds per square inch. It the uncoiler is stopped, as for welding on a new coil, the tension on the strip in the looper increases and, when the pressure in the cylinder 12 reaches 95 pounds per square inch, the hoist motor 54 will be started in the lowering direction. The motor will continue to lower the carriage, its speed being controlled by the pressure controlled rheostat I20, until the welding oi the strip is completed and the feed of strip into the looper is again started. This will cause the tension in the strip to decrease and the piston I06 to rise again until the pressure in the cylinder l2 drops to the point where the hoist motor starts to hoist carriage 30 again.

The pneumatic mounting of roller 08 allows the avoidance of undesirably high tensions in the strip upon the stoppage of feed into the looper due to the inability oi the hoist motor to come up to speed quickly enough to pay out the strip as required. When the strip entering the looper suddenly is stopped, piston I06 will travel downwardly in the cylinder under the influence of a relatively small increase in tension in the strip. When the pressure in the cylinder, which is rapidly increased by such downward travel of the piston, reaches 105 pounds per square inch, relief valve II4 will open. By the time motor will have reached the speed necessary to lower carriage 30 at a rate to compensate for the speed of travel of the strip from the looper, the piston I06, which may be near the bottom of the cylinder, will cease to travel with respect to the cylinder. Air will then be admitted at 100 pounds per square inch through valve IIO, now opened by cam I22, and such air will again raise piston I06 to its normal position. It is to be understood that the length of cylinder 12 and consequently the length of stroke of piston I08 will be determined by the length of time it takes the hoist motor to reach the speed where the motion oi the carriage 30 up or down compensates for the difference in speed of the strip at the entering and exit ends of the looper.

I Whereas the above control circuit for the looper is usually preferred, since: it is fully automatic for both directions or movement of the looper carriage, in some instances it is desired that travel of the looper carriage downward be automatically controlled, but that its travel upward be manually controlled. The circuit shown in Figure 8 is one which may be used for such alternative mode of control of the looper. In that figure, hoist motor 54', having an armature I30 and a shunt field I32, is supplied from an I electric current source L1 and L2. The speed of the motor is controlled by a variable resistance I48, in series with the armature, controlled by an air cylinder device I09 similar to means I" in Figure 7, the connection to the air cylinder device being such that resistance H8. is controlled to provide a resistance which varies inversely as the pressure in the air cylinder 12. Thepressure responsive device I36, similar to means I36 in Figure '7, is, in this instance, connected to a three pole contactor I52, connected as shown, so that when the three pole double throw a switch I50 is in the upper position the motor When switch I00 is in such position, the appsratus is in condition for the automatic lowering oi the looper carriage upon an increase in tension in the strip. When switch I00 is in its lower position, however, the circuit is made operative only for manual raising of the carriage, the field being connected to the current source in such relationship as to reverse the motor and the armature being connected through manually operated rheostat IN, upper limit switch ll, and wire I08, the speed of raising the carriage thus being controlledmanually by rheostat I. It will be apparent that with either control circuit disclosed the same advantage of avoiding undesirably high tension in the strip upon the stoppage of feed of the strip through the looper and the consequent downward travel oi the looper carriage are obtained.

Whereas I have shown and described preferred modifications of the looper of the present invention, it is obvious that numerous variations thereof are possible within the scope of the invention. I, iihererigre, desire to claim as new the following.

1. A looper for gathering a localized excess of elongated material while permitting its travel in v opposing head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head to cushion the elongated material, power means for causing the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, and means responsive to changes in position of the yieldingly mounted roller in response to a predetermined increase in tension in the strip in the looper automatically to initiate said power means.

2. A looper for gathering a localized excess oi elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried, means resiliently mounting said movable roller to cushion the elongated material, said last named means comprising a pneumatic cylinder, means i'or introducing gas under pressure into the cylinder, power means for causing the first head to travel relatively toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, and means responsive to changes in the pressure of the gas within the cylinder consequent to changes in position of the resiliently mounted roller in response to predetermined changes in tension in the strip in the looper automatically to initiate said power means.

3. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head. spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in the direction toward the opposing head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head, said mounting means comprising a fluid pressure cylinder, power means for causing the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, means to admit fluid under pressure to the cylinder so as to urge the movable roller away from the opposing head, and means responsive to fluid pressure within the cylinder and operative upon the development of a predetermined maximum pressure within the cylinder to initiate operation of the power means.

4. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head, said mounting means comprising a fluid motor having a fluid cylinder and a piston and piston rod reciprocable therein, the movable roller being connected to the piston rod, means to admit fluid under a predetermined pressure to the fluid cylinder to urge the movable roller toward the head on which it is mounted when such roller projects more than a predetermined distance therefrom, a power means for causin the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, and means connected to said power means to cause its initiation in response to a predetermined increase in the tension in the strip in the looper, said last named means comprising a pressure responsive means connected to the fluid cylinder and operative upon the fluid in the fluid cylinder reaching a predetermined maximum pressure.

5. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head, said mounting means comprising a fluid motor having a fluid cylinder and a piston and piston rod reciprocable therein, the movable roller being connected to the piston rod, means to admit fluid under a predetermined pressure to the fluid cylinder to urge the movable roller toward the head on which it is mounted when such roller projects more than a predetermined distance therefrom, a fluid pressure relief valve connected ing the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper,

and means connected to said motor to cause its initiation in response to a predetermined increase in the tension in the strip in the looper, said last named means comprising a pressure responsive switch connected to the fluid motor, and a pressure operated rheostat connected to such fluid motor, the pressure operated switch and the pressure operated rheostat being connected in the power circuit of the electric motor; the length of travel of the piston in the fluid motor being sufficient to allow the electric motor to attain sufflcient speed to permit the elongated material to be paid out without undue increase in tension thereof before the movable roller reaches the limit of its travel with respect to the head on which it is mounted.

6. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried, and means mounting said movable roller for yielding movement toward the opposing head, said mounting means comprising a pneumatic motor having a cylinder piston and piston rod reciprocable therein, the movable roller being connected to the piston rod, means to admit gas under a predetermined pressure to the pneumatic motor cylinder to urge the movable roller toward the head on which it is mounted, said last named means comprising a source of gas under pressure, a pressure regulating valve and a shut-01f valve connected in series with such source and between it and the pneumatic motor, the pressure regulating valve being set at a first predetermined pressure and the shut-off valve being normally closed, a cam driven in synchronism with the piston of the motor for cooperation with the shut-oif valve, said cam having such configuration as to open the valve when the movable roller projects more than a predetermined distance from the head on which it is mounted and to close the valve when the roller is closer than such predetermined distance from the head, a gas pressure relief valve connected to the pneumatic motor cylinder and set at a second predetermined pressure somewhat higher than the first predetermined pressure, an electric motor for causing the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, means connected to said motor to cause its initiation in response to a predetermined increase in the tension in the strip in the looper, said last named means comprising a pressure responsive switch connected to the pneumatic motor and operative upon the attainment of a third predetermined pressure somewhat lower than the first predetermined pressure, and a pressure operated rheostat connected to such pneumatic motor, such rheostat being operative to increase the speed of the electric motor with an increase in pressure in the pneumatic motor, the length of travel in the piston in the pneumatic motor being suificient to allow the electric motor to attain sufficient speed to permit the elongated material to be paid out without undue increase in tension thereof before the movable roller reaches the limit of its travel with respect to the head on which it is mounted.

'7. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the opposin head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head to cushion the elongated material, power means for causing the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, means responsive to changes in position of the yieldingly mounted roller in response to a predetermined increase in tension in the strip in the looper automatically to initiate said power means, and means for rendering the power means for causing the first head to travel toward the second head to become inoperative when the heads reach a position closely adjacent to each other.

8. In the combination of mechanism for feeding elongated material including a looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension, means feeding the material into the looper, means for feedin the material out of the looper, means to which the material is fed from the looper for the continuous treating of the material, and means for feeding the material into and out oi the looper and through the treatin means including motors for driving such feeding means, the improved looper which comprises a first loop-forming head and a second loop-form ng head opposed thereto, means jnder to initiate the power means to cause the mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head. at least one of the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried. means mounting said movable roller for yielding move-' ment toward the opposing head to cushion the elongated material. said last named means comprisine a fiuid cylinder. power means for causing the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, means responsive to changes in the pressure in the fluid within the cylinder conseuuent to changes in the position of the yieldincly mounted roller automatically to initiate said power means. a switch connected in the control circuits of the motors driving the feeding means for the elongated material through the processing line and the looper, said switch being normally closed to render such circuits operative, and means operative upon travel of the movable roller at least substantially to its extreme retracted position as a result of the breakage oi the material to open the switch and thus stop the feed motors.

9. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predeterminedtension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first oi said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head, power means for selectively causing the first head to travel toward or away from the second head, and means responsive to changes in the force imposed upon the mounting means for the movable roller as a result of changes in the tension on the elongated material in the looper so constructed and arranged that an increase in tension in the material past a predetermined maximum amount automatically causes the power means to move the first head toward the second head and so that an increased tension in the elongated material past apredetermined minimum amount causes the first head automatically to move away from the second head.

10. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the matic cylinder, means for introducing gas under Til pressure into the cylinder, power means for causing the first head to travel toward and away from the second head, means responsive to a predetermined maximum pressure in the pneumatic cylfirst head to travel toward the second head, and means responsive to a predetermined minimum pressure in the pneumatic cylinder to initiate the power means to cause the first head to move away from the second head.

11. A looper for gathering a localized excess of elongated material while permitting its travel in the direction'of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head, said mountin means comprising a fluid motor having a fluid cylinder and a piston and piston rod reciprocable therein, the movable roller being connected to the piston rod, means to admit fluid under a predetermined pressure to the fiuid cylinder to urge the movable roller toward the head on which it is mounted when such roller projects more than a predetermined distance therefrom, an electric motor for causing the first head to travel toward and away from the second head, and means connected to said electric motor to cause its initiation in the proper direction and at the proper speed upon predetermined changes in the strip in the looper to maintain the tension Within allowable limits, said last named means comprising a pressure responsive switch in the motor circuit and connected to the fluid cylinder operative by a predetermined maximum pressure to start the electric motor for causing the first head to move toward the second head and operative upon a certain minimum pressure to start the motor to cause the first head to travel away from the second head, and pressure responsive rheostat means connected to the fiuid cylinder to vary the motor speed in accordance with the pressure upon approach of the first head'toward the second head and inversely in accordance with the pressure upon travel of the first head away from the second head.

12. A looper for gathering a localized excess of elongated material while permittin its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one of the rollers being mounted for movement in a, direction toward the opposing head and with respect to the head on which it is carried, means resiliently mounting said movable roller to cushion the elongated material, said last named means comprising a pneumatic cylinder, means for introducing gas under pressure into the cylinder, power means for causing the first head to travel toward the second head to enable material to be paid out of the looper at a rate faster than it enters the looper, and means responsive to changes in the pressure of the gas within the cylinder consequent to changes in position of the resiliently mounted roller in response to predetermined changes in tension in the strip in the looper automatically to initiate said power means, selectively operable means for reversing the direction of travel of the heads by the power means, and means for manually controlling the speed of travel at which the first head is moved away from the second head by the power means.

13. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a second loop-forming head opposed thereto, means mounting the first or said heads for travel toward and away from the second head, spaced loop-forming rollers on each head, at least one 01' the rollers being mounted for movement in a direction toward the opposing head and with respect to the head on which it is carried, means mounting said movable roller for yielding movement toward the opposing head, said mounting means comprising a fluid motor having a fluid cylinder and a piston and piston rod reciprocable therein, the movable roller being connected to the piston rod, means to admit fluid under a predetermined pressure to the fiuid cylinder to urge the movable roller toward the head on which it is mounted when such roller projects more than a predetermined distance therefrom, a reversible electric motor for causing the first head to travel toward or away from the second head, a source of current therefor, means connected to the electric motor to cause its initiation in response to a predetermined increase in the tension in the strip in the looper to move the first head toward the second head, said last named means comprising a pressure responsive switch connected to the fiuid cylinder and in the current supply circuit of the electric motor and operative when the fluid reaches a predetermined maximum pressure, a manually operative reversing switch for the electric motor which disconnects it from the circuit for automatically causing the first head to approach the second head and connects it to a circuit whereby it is driven in the opposite direction to cause the first head to separate from the second head, and manually operated rheostat means in the latter circuit to control the speed at which the first head is separated from the sec" ond head.

14. A looper for elongated material compris ing a first loop-forming head and a second loopforming head opposed thereto, means mounting the first of said heads for travel toward and away from the second head, power means for causing the first head to travel toward the second head to permit material to be taken out of the looper at a rate faster than it enters the looper, means for mainaining the material under tension in the looper, a detector for determining the amount of tension on the material, and means operable by said detector and responsive to a predetermined increase in tension in the material in the looper to cause the power means to move the first head toward the second head at a rate sufiicient to permit the material to pass out of the looper faster than it enters therein.

15. A looper for gathering a localized excess of elongated material while permitting its travel in the direction of its length and maintaining it under a predetermined tension comprising a first loop-forming head and a, second loop-forming head opposed thereto, means mounting the first 01' said heads for travel toward the second head to permit material to be taken out of the looper at a rate faster than it enters the looper, power means for causing the first head to travel toward and away from the second head, means for maintaining the material under tension in the looper, a detector for determining the amount of tension on the material, means operable by said detector and responsive to a predetermined increase in tension in the material in the looper to cause the power means to move the first head toward the second head at a rate sufilcient to permit the material to pass out of the looper fasterthan it enters therein, and selectively operable means for allowing the separation of the first head from the second head under manual control.

. WILLIAM H. MURSCH.

REFERENCES QITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Ferm Apr. 28, 1942

Images