US3462831A

US3462831A - Device for and method of making a coil construction

Info

Publication number: US3462831A
Application number: US671708A
Authority: US
Inventors: Benton A Whiteman
Original assignee: Reynolds Metals Co
Current assignee: Reynolds Metals Co
Priority date: 1967-09-29
Filing date: 1967-09-29
Publication date: 1969-08-26
Anticipated expiration: 1986-08-26

Description

AugQ-Z G, 1969 B. A; WHITEMAN DEVI E FOR AND METHOD OF MAKING A COIL CONSTRUCTION 3 Sheets-Sheet 1 Filed Sept. 29, 1967 I IVENTOR ENTON A. WHITEMAN j l K 9414 HIS ATTORNEYS Aug. 26, 1969 B. A. WHITEMAN 3,462,331

' vDEVICE FOR AND METHOD OF MAKING A'COIL CONSTRUCTION Filed Sept. 29,. 1967 l I s Sheets-Sheet 2 INVENTOR BENTON A. WHITEMAN HIS ATTORNEYS Aug. 26,

I a. A. WHITEMAN DEVICE FORANDMETHQD OF MAKING A COIL CONSTRUCTION Filed Sept. 29. 1967 3 Sheets-Sheet 5 I if 411 INVENTOR BENTON A. WHITEMAN HIS ATTORNEYS United States Patent Ofitice 3,462,831 DEVICE FOR AND METHOD OF MAKING A COIL CONSTRUCTION Benton A. Whiteman, Richmond, Va., assignor to Reynolds Metals Company, Richmond, Va., a corporation of Delaware Filed Sept. 29, 1967, Ser. No. 671,708 Int. Cl. B23 19/00, 21/00 US. Cl. 29-605 12 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a device which controls the unwinding of an elongated strip of material from a supply roll thereof during the coiling of such strip to define a coil construction wherein the device has control means which acts directly against the outer periphery of such supply roll to provide control unwinding of the elongated strip.

CROSS-REFERENCE TO RELATED APPLICATION This application is related to copending patent application, Ser. No. 497,069, now Patent No. 3,412,450, filed Oct. 1 8, 1965.

BACKGROUND OF THE lNVENTION During the unwinding of an elongated strip of material from a supply roll thereof it has been found that if the supply roll can be accurately controlled so that each section of elongated strip material that is unwound therefrom is unwound in a guided manner, it is considerably easier to then coil such unwound section to form a coil construction having a desired configuration.

SUMMARY BRIEF DESCRIPTION OF THE DRAWING The accompanying drawing illustrates a present preferred embodiment of this invention, in which:

FIGURE 1 is a perspective view of an exemplary strip conductor coil construction made using the improved device of this invention;

FIGURE 2 is a perspective view illustrating one exemplaiy embodiment of a coil winding apparatus which is used with the improved device of this invention to form the coil construction of FIGURE 1;

FIGURE 3 is a fragmentary perspective view illustrating electrical leads attached to an elongated strip of electrically conductive material used in forming the coil construction of FIGURE 1;

FIGURE 4 is a view on the line 44 of FIGURE 2 particularly showing the manner of using the device of this invention to control the unwinding of an elongated strip of electrically conductive material from a supply roll thereof;

FIGURE 5 is a fragmentary View showing the manner of coupling a freely rotatable core carrying mandrel with drive means therefor;

FIGURE 6 is a fragmentary view showing carriage 3,462,831 Patented Aug. 26, 1969 means comprising the device of this invention latched in position above the supply roll;

FIGURE 7 is an enlarged fragmentary view particularly illustrating the latch means used to latch the carriage means in position;

FIGURE 8 is an enlarged fragmentary view in elevation particularly illustrating the carriage means comprising the device of this invention held against the sup ply roll;

FIGURE 9 is an enlarged fragmentary end view of the device of this invention as illustrated in FIGURE 8; and

FIGURE 10 is a sectional view on the line 10-10 of FIGURE 8.

DESCRIPTION OF THE ILLUSTRATED EXEMPLARY EMBODIMENT An exemplary strip conductor coil construction or coil made while using the device of this invention is shown in FIGURE 1 and indicated generally by the reference numeral 25. The coil 25 comprises a tubular and substantially right circular cylindrical core element 26 which has a ribbon or strip 27 of electrically conductive material wound thereon in a manner as will be hereinafter described. The strip 27 has inner end means comprising an inner electrical lead 30 fixed thereto and outer end means comprising an outer electrical lead 31 suitably fixed thereto. The completed coil 25 is adapted to be installed in an associated electrical system with its

leads

30 and 31 suitably electrically connected in a known manner.

In many applications the housing means, or the like, provided immediately adjacent the coil 25 may have a closely controlled configuration requiring that coil 25 also have an outer peripheral configuration which is controlled in a corresponding manner. The improved device of this invention is designated generally by the numeral 29 and provides means for accurately controlling the strip 27 as it is unwound from its supply roll 34 to thereby effectively control the configuration of coil 25 as each associated section of strip 27 is wound on an associated core 26. The manner in which the device 29 operates to provide such controlled unwinding will be explained in detail subsequently.

In the exemplary coil 25 presented in FIGURE 1 the under side of the elongated strip of conductive material 27 preferably has a strip or coating of insulating material prelaminated thereagainst before strip 27 is wound on the core element 26 to provide electrical insulation means between adjacent coils of the strip of conductive material 27. However, if desired, strip 27 can be wound on core element 26 in unison with a separate strip of insulating material so that the strip of insulating material is interleaved between adjacent coils of the strip of conductive material 27 to electrically insulate adjacent coils of strip 27 from each other.

The exemplary coil winding apparatus used in forming the strip conductor coil construction 25 of FIGURE 1 in a substantially continuous manner is generally indicated by the reference numeral 32 in FIGURE 2. The apparatus 32 includes a frame structure 33 rotatably carrying a supply roll 34- of conductive strip material 27. As previously stated, the strip material 27 preferably has a strip or coating 35 of insulating material laminated to its lower surface, as illustrated in FIGURE 3, to provide electrical insulation between adjoining coils.

The tubular core elements 26 may be made of cardboard or the like and are contained in a suitable hopper means or hopper 36. The hopper 36 has a downwardly extending chute 37 extending from its lower end. Each core element is adapted to be serially fed into a retainer 38 provided at the terminal lower end of chute 37 and supported to enable it to be easily picked up by an associated mandrel in a manner to be subsequently described.

As illustrated in FIGURE 2, the frame structure 33 carries a rotary table 39 which is adapted to be indexed in a rotary manner about a fixed vertical axis. The table 39 carries three actuating means or actuators shown as three fluid cylinders each designated by the numeral 40.

Each cylinder 40 has a telescoping rod 41 which carries support means enabling coil 25 to be formed thereon and such Support means comprises a radially expandable and freely rotatable mandrel 42 carried at the terminal end of telescoping rod 41. Each cylinder 40 is adapted to extend and yieldingly hold its mandrel 42 into operative engagement with drive means therefor in a known manner.

The table 39 is adapted to index the mandrels 42 through three

stations

45, 46, and 47. When a mandrel 42 is indexed to station 45, the associated cylinder 40 extends associated rod 41 radially outwardly telescoping mandrel 42 within a core element 26 supported within retainer 38 at the lower end of hopper 36.

When the mandrel 42 at station 45 has a core 26 thereon, the associated piston rod 41 is retracted by cylinder 40 so that the core 26 is carried by mandrel 42 out of the retainer 38 whereby such retracted mandrel can be indexed from station 45 to winding station 46. Hopper 36 contains a plurality of cores 26 which are adapted to be serially dropped into retainer 38 through chute 37 as previously mentioned. As each core 26 is removed by an associated mandrel from retainer 38 another core 26 drops in its place.

With the core carrying mandrel 42 now at station 46, the piston rod 41 thereof is extended to interconnect manrel 42 by suitable driven clutch means 50 provided in its terminal outer end to suitable cooperating driving clutch means 51 provided on a rotatable drive shaft 53 comprising winding apparatus 32, see FIGURES 1 and 5. As the drive shaft 53 is rotated, the same rotates mandrel 42 at station 46 to cause elongated strip 27 to be wound on the core 26 carried by the rotating mandrel 42 to define coil construction 25. The elongated strip 27 is unwound from supply roll 34 and is held in a substantially vertical plane by the device 29 of this invention to enable forming of coil construction 25 in the desired manner.

After a completed strip conductor coil 25 has been formed on mandrel 42 at station 46, the associated piston rod 41 is retracted to thereby disconnect the driven mandrel 42 from drive shaft 53 and specifically to thereby move driven clutch means 50 away from driving clutch 51, whereby the retracted mandrel 42 is then indexed from station 46 to station 47. With the completed strip conductor coil 25 on mandrel 42 at station 47, the associated piston rod 41 is extended whereby the strip conductor coil 25 is held in a position at the station 47 so that a pair of stripping members each designated by the numeral 54-, see FIGURE 2, can strip the finished strip conductor coil from mandrel 427 The stripping members 54 are pivotally mounted to a support 55 by suitable pivot pins respectively carrying pinion gears disposed in meshing relation with each other. One of the stripping members 54 is interconnected to a piston rod 56 adapted to be extended and retracted by a fluid cylinder 57 carried by support 55. Thus, with a completed strip conductor coil 25 being held at station 47 by an extended mandrel 42, cylinder 57 is actuated to telescope its rod 56 outwardly and through the action of the above mentioned pinion gears stripping members 54 are brOught into clamping engagement in a known manner on opposite sides of coil 25.

With the strip conductor coil 25 now firmly clamped between the stripping members 54 retraction of the piston rod 41 of the mandrel 42 at station 47 pulls such mandrel out of the core 26 of the completed strip conductor coil 25 so that the particular mandrel 42 can be subsequently indexed to the station 45 by indexing table 39. With the mandrel 4-2 at station 47 now retracted from within core 26 of the completed strip conductor coil 25, the cylinder 57 can be dcactuated to return the stripping members 54 to the open position illustrated in FIGURE 2 whereby such members drop the completed strip conductor coil 25 onto a chute means 58. The completed strip conductor coil 25 moves down chute 58 to a table 60 for subsequent testing, packaging and the like of the completed strip conductOr coils 25 produced by apparatus 32.

As illustrated particularly in FIGURE 4, the elongated strip 27 is adapted to be fed from its supply roll 34 around a turn roll 61 and through a suitable slack reducing and tension applying device designated generally by the numeral 62. Device 62 has a freely rotatable roller 63 carried by a lever 64 which is pivotally mounted to the frame 33 of apparatus 32 by a pivot means 65.

The elongated strip 27 continues from roller 63 around a pair of rolls and 71 and through a device designated generally by the numeral 72 which attaches leads 30 and 31 to the elongated strip 27 in a known manner. The strip 27 continues beyond the lead attaching device 72 between a combination guide means and bearing surface means designated by the numeral 73 and a table 74 to winding station 46. The strip 27 moves from supply roll 34 to winding station 46 so that side edge means thereof is kept in a substantially vertical plane for reasons which will be explained in detail hereinafter.

Apparatus 32 also has a pair of taping head means designated by the

numerals

75 and 76 which are employed to start strip 27 on core 26 as well as tape the final coil or layer of coil construction 25 in position to prevent unwinding thereof. The manner is which lead attaching device 72, guide 73, table 74, and taping heads 75 and 76 are utilized in forming coil construction 25 will be more thoroughly understood by referring to the detailed description of similar components fully disclosed in the copending patent application Serial No. 497,069 referenced above. However, a detailed understanding of the operation of components 72-76 is not necessary to thoroughly understand the operation of the apparatus or device 29 of the present invention.

The slack reducing and tension applying device 62 has a tension spring 80 which has one end attached to lever 64 as shown at 81 and its opposite end is attached to the frame 33 at 82. Spring 80 operates to continuously yieldingly urge lever 64 in a clockwise direction about its pin 65 and thereby cause the roller 63 carried at its terminal swinging end to apply tension on the elongated strip 27 as it moves to winding station 46.

Device 62 also has a pair of adjustable stops arranged on opposite sides of lever 64. Each adjustable stop comprises block means or a block 83 which is suitably fastened to frame structure 33 and a threaded stop bolt 84 which is threaded through a cooperating threaded opening in block 83 so as to be readily adjustable toward and away from pivoted lever 64. With this arrangement it is readily possible to thread each stop bolt 84 any desired amount toward and away from pivoted lever 64 and thereby control the are through which pivoted lever 64 is allowed to swing under the influence of spring 80 and the force exerted by strip 27 as it moves over roller 63 at the terminal end of lever 64.

The configuration of coil construction 25 can be more accurately and economically controlled for many applications of such coil construction by controlling the manner in which the elongated strip 27 is moved to winding station 46 and wrapped around an associated core 26 to define the coil construction. In particular, it has been found that it is preferable to control the unwinding of elongated strip 27 from supply roll 34. The exemplary device of this invention used to control such unwinding is designated generally by the numeral 29 as previously mentioned and comprises support means shown as shaft means 86 for supporting supply roll 34 for substantially free rotation therearound and control means designated generally by the numeral 87 and acting against the outer periphery of supply roll 34.

Support shaft means or shaft 86 supports the supply roll 34 for free rotation about a fixed axis of rotation. In addition, the outside diameter of shaft 86 is slightly smaller than the inside diameter of the core means carrying supply roll 34 to thereby allow free axial movement of the supply roll 34 along shaft 86 and hence along the fixed axis of rotation defined by shaft 86. Thus, supply roll 34 is freely rotatable about shaft 86 and such supply roll is also freely axially movable along shaft 86 thereby enabling the control means or device 87 to be used to continuously axially position supply roll 34 so that the outer coil of such supply roll 34 is always maintained in the same substantially fixed vertical plane.

The control means 87 of this exemplary embodiment of the invention comprises guide means shown as a pair of freely rotatable rollers each designated by the numeral 90 and bearing surface means shown as another freely rotatable roller designated generally by the numeral 91. The guide roller 90 and bearing roller 91 are carried on suitable carriage means designated generally by the numeral 92 and which comprises the control means 87.

Carriage means or carriage assembly 92 is supported for movement substantially radially toward and away from supply roll 34 on suitable track means comprised of a vertically arranged plate means or plate assembly designated by the numeral 94 which supports the carriage assembly 92 for vertical movement in a fixed substantially vertical plane and along a substantially rectilinear path in a manner as will be subsequently described.

The device 29 also comprises urging means shown as a tension spring 95 which acts together with the force of gravity to pull carriage assembly 92 toward supply roll 34. The tension spring 95 has its upper end fastened to a suitable hook 96 which is fixed to carriage assembly 92 and has its lower end fastened to a pin 97 which is threaded into a cooperating threaded opening in plate assembly 94 as shown at 100; and, spring 95 is stretched therebetween to continuously pull the carriage assembly 92 toward the supply roll 34.

As seen in FIGURES 9 and 10, carriage assembly 92 has an outwardly extending arm designated by the numeral 101 which supports

rollers

90 and 91. Arm 101 has a threaded blind hole 102 adjacent its inner end which is adapted to receive the threaded end portion 103 of a shaft 104 which supports the inner guide roller 90 at its terminal end. The outer roller 90 is supported on a shaft 105 which has a threaded terminal end portion 106 which extends through an opening 107 in arm 101 and is suitably fastened in position by a pair of nuts each designated by the numeral 110 and which are threaded on threaded portion 106 so as to fasten shaft 105 in position on outwardly extending arm 101.

Arm 101 also has a pair of parallel legs each designated by the numeral 111 extending downwardly therefrom in parallel spaced apart relation and adapted to carry roller 91 therebetween. Roller 91 is carried on a shaft 112 which is supported between the downwardly extending legs 111 so that roller 91 is freely rotatable.

Thus, it is seen that outwardly extending arm 101 and the

rollers

90 and 91 supported thereon are supported essentially in a cantilevered manner from the carriage assembly 92.

The carriage assembly 92 and hence

rollers

90 and 91 are adapted to move in a substantially fixed vertical plane and in a rectilinear path so that as the outer layer of elongated strip 27 leaves its supply roll 34 it is always held in a substantially fixed plane. This action is achieved because of the manner in which the carriage assembly 92 is supported for precise vertical movement.

The carriage assembly 92 is maintained at a predetermined desired position with respect to the outer periphery of supply roll 34 by the bearing surface means or roller 91 engaging its outer circumference. As the 6 spring and the force of gravity act against the carriage assembly 92, the roller 91 is urged and held against the outer circumference of supply roll 34 to thereby position the guide rollers 90 on opposite sides of the freely rotatable and freely axially slidable supply roll 34 and thus continuousy axially position such supply roll causing each side edge means of the elongated strip 27 to remain in a substantially fixed vertical plane for easier winding of strip 27 on an associated core 26.

The plate assembly 94 has a pair of parallel spaced apart vertically arranged wheel receiving groove means each designated by the same numeral 114. Plate assembly 94 may comprise a portion of the supporting structure 33 of apparatus 32 or may comprise a separate unit which is suitably fastened in position to supporting structure 33.

Plate assembly 94 also has an elongated opening preferably arranged between groove means or grooves 114 and arranged parallel to grooves 114. Elongated opening 115 is adapted to receive fastening means therethrough which is used to fasten a first carriage 116 and a second carriage 118 comprising the carriage assembly 92.

The first carriage 116 of this exemplary embodiment of the invention has a plurality of four rotatable wheel means or wheels each designated by the numeral 117. Carriage 116 is adapted to move along the front surface of plate assembly 94 so that its wheels 117 are guided by grooves 114 to thereby guide carriage 116 in a substantially rectilinear vertical path.

The second carriage 118 also has a plurality of four rotatable wheel means or wheels each designated by the numeral 121. Carriage 118 is arranged against the rear surface means of the plate assembly 94.

The fastening means provided for

fastening carriages

116 and 118 together to define the carriage assembly 92 comprises a fastening plate 123 which has a width allowing it to be freely inserted through elongated opening 115. Plate 123 has carriage 116 fixed thereto by a threaded bolt 124 which extends through an opening 125 in carriage 116 and is threaded into a cooperating threaded opening 126 in the forward face of plate 123. Similarly, carriage 118 is fixed to the rear portion or face of plate 123 by a pair of bolts each designated by the numeral 130 and each extending through an associated opening 131 extending through carriage 118 and each bolt 130 is threaded into a cooperating threaded opening 132 provided in plate 123.

The above described structural arrangement fastens

carriages

116 and 118 on opposite sides of plate assembly 94 and the arrangement of fastening member 123 is such that the entire carriage assembly 92 can be moved vertically up and down along plate assembly 94 in an unobstructed manner.

As seen in the drawings, the

carriages

116 and 118 have their respective wheels engaging opposite side surface means of vertical plate means or assembly 94. As previously mentioned, the wheels 117 of carriage 116 are adapted to be received within grooves 114 in the front surface of plate assembly 94 so as to guide carriage 116 as Well as the entire carriage assembly 92 vertically up and down along the vertical plate assembly 94. It will be appreciated that the above described structural arrangement provides a precise movement for the guide means comprised of guide rollers 90 and the bearing surface means comprised of bearing surface roller 91.

Each

carriage

116 and 118 comprising carriage assembly 92 in this example of the invention preferably has four wheels, as previously mentioned. The wheels 117 of carriage 116 are suitably rotatably supported about a pair of axles each designated by the numeral 135. Similarly, wheels 121 of carriage assembly 118 are also rotatably supported about a pair of axles each designated by the numeral 136. Each set of axles 135 of carriage 116 and axles 136 of carriage 118 are arranged in spaced apart relation so that with their associated wheels installed in position a broad stable base is provided for each individual carriage 116 and hence for the entire carriage assembly 92. This structural arrangement assures that the movement of

rollers

90 and 91 is less affected by minor imperfections in plate assembly 94 as such carriage assembly moves vertically up and down because

wheels

135 and 136 provide a broad stable base for carriage assembly 92.

Means is provided for latching the carriage assembly 92 in its uppermost position, see FIGURE 7. In this example of the invention, such means comprises a pin 140 fixed to the upper end portion 116 of carriage assembly 92 and a suitable latch 141 supported at the upper end portion of plate assembly 94. The latch 141 is pivotally mounted about a pivot screw 142 and has a coiled spring 143 which acts between a pin 144- provided on the plate assembly 94 and latch 141 so as to continuously urge latch 141 so that its hooking end portion 145 extends substantially across the upper end of elongated opening 115 in the plate assembly 94.

Upon raising the carriage assembly 92 to its uppermost position, as illustrated in FIGURE 6, the hooking end portion 145 of latch 141 latches beneath pin 140 and holds the carriage assembly 92 in its uppermost position allowing easy installation of a new supply roll 34, for example. When it is desired to lower the carriage assembly 92 it is merely necessary to rotate latch 141 in a clockwise manner releasing its hooking end portion 145 from beneath pin 140 and allowing the carriage assembly 92 to return to its lowermost position with bearing surface roller 91 engaged against the top circumferential surface of the new supply roll 34 and the guide rollers 90 engaging along opposite side edge portions of the new supply roll 34.

Thus, it is seen that the device 29 of this invention con tinuously repositions freely rotatable supply roll 34 axially along its supporting shaft 86 so that as each outer layer leaves the supply roll 34 it is maintained in a substantially fixed vertical plane. This controlled unwinding of supply roll 34 enables easier forming of coil construction 25.

In addition to the above described action of rollers 90 of device 29 the roller 91 of such device in addition to preventing overrunning of supply roll 34 also prevents the spring 95 and the force of gravity from moving the guide rollers 90 too far radially inwardly toward the center of supply roll 34 during the winding of coil construction 25.

Terms such as outwardly, inwardly, upwardly, downwardly, vertically, horizontally, front, rear, and the like, have been used in this disclosure of the invention for ease of description and merely to correspond to the arrangement and operation of component parts as illustrated in the drawings and such terms should not be considered as limiting the scope of this invention in any way.

Thus, it is seen that an improved device and method used in making a coil construction have been provided by this invention.

While the present preferred embodiments of this invention, and methods of practicing the same, have been illustrated and described, it will be recognized that this invention may be otherwise variously embodied and practiced within the scope of the following claims.

What is claimed is:

1. In a strip conductor coil winding apparatus a device for controlling the undwinding of an elongated strip of material from a supply roll thereof during the coiling of said elongated strip to define a coil construction, said device comprising, support means supporting said supply roll for rotation, and control means acting against the outer periphery of said supply roll to provide a controlled unwinding of said elongated strip, said support means comprising shaft means supporting said supply roll for free rotation about a fixed axis of rotation while allowing free axial movement of said supply roll along said fixed axis and said control means engages and continuously axially positions said supply roll to provide said controlled unwinding, said control means comprising: carriage means supported for movement substantially radially toward and away from said supply roll, guide means carried by said carriage means and engaging side edge means of said elongated strip during said unwinding, bearing surface means carried by said carriage means and engaging the outer circumference of said supply roll to prevent said supply roll from overrunning, and urging means yieldingly and continuously urging said carriage means toward said supply roll to thereby yieldingly urge said bearing surface means against said outer circumference while simultaneously holding said guide means against said side edge means throughout said unwinding.

2. A device as set forth in claim 1 further comprising vertically arranged track means supporting and guiding said carriage means for vertical movement and in which, said carriage means is supported by a plurality of rotatable wheel means arranged to provide a 'broad stable base for said carriage means so that said carriage means and said guide means will be precisely located relative to said track means, said guide means comprises a pair of freely rotatable rollers supported on said carriage means so as to engage opposite side edges of said elongated strip, and said bearing surface means comprises another rotatable roller supported on said carriage means so as to engage the outer circumference of said supply roll, whereby said broad stable base provided by said wheel means assures said carriage means and rollers carried thereby are always precisely located relative to said track means to thereby precisely locate said elongated strip in a corresponding manner as it is unwound from said supply roll.

3. A method of forming an elongated strip of material on a coil winding apparatus to define a coil construction comprising the steps of, providing said coil winding apparatus, providing a supply roll of said elongated strip, providing support means for said supply roll, supporting said supply roll on said support means for free rotation to enable unwinding thereof during coiling of a section of said elongated strip to form said coil construction, providing control means adapted to act against said supply roll, and controlling the unwinding of said elongated strip with said control means to thereby effectively control the configuration of said coil construction, said step of providing support means comprises providing shaft means supporting said supply roll for free rotation about a fixed axis of rotation while allowing free axial movement of said supply roll along said fixed axis and said controlling step comprises engaging and continuously axially positioning said supply roll to provide said unwinding in a controlled manner, said step of providing control means comprises the further steps of, providing carriage means supported for movement substantially radially toward and away from said supply roll, providing guide means carried by said carriage means and engaging side edge means of said elongated strip during said unwinding, providing bearing surface means carried by said carriage means and engaging the outer circumference of said supply roll to prevent said supply roll from overrunning, and providing urging means yieldingly urging said carriage means toward said supply roll, whereby during said controlling step said urging means yieldingly and continuously urges said carriage means toward said supply roll to thereby urge said bearing surface means against said outer circumference while simultaneously holding said guide means against said side edge means through said unwinding.

4. A method as set forth in claim 3 comprising the further steps of, providing track means for said carriage means arranged in a substantially vertical first plane and supporting said carriage means for substantially frictionless movement along said track means so that during said controlling step said guide means assures said elongated strip is unwound from said supply roll so that it moves in a second plane substantially parallel to said first plane.

5. A device for controlling the unwinding of an elongated strip of material means from a supply roll thereof comprising, support means supporting said supply roll for rotation, and control means acting against the outer periphery of said supply roll to provide a controlled un- Winding of said elongated strip, said supported means comprising shaft means supporting said supply roll for free rotation about a fixed axis of rotation while allowing free axial movement of said supply roll along said fixed axis and said control means engages and continuously axially positions said supply roll to provide said controlled unwinding, said control means comprising a pair of cooperating freely rotatable guide rollers engaging and guiding opposite side edge means of said elongated strip during said unwinding and as said supply roll decreases in size.

6. A device as set forth in claim in which said control means comprises bearing surface means yieldingly urged against said supply roll and acting substantially radially toward the center of said supply roll to prevent said supply roll from overrunning.

7. A device for controlling the unwinding of an elongated strip of material means from a supply roll thereof comprising, support means supporting said supply roll for rotation, and control means acting against the outer periphery of said supply roll to provide a controlled un- Winding of said elongated strip, said support means comprising shaft means supporting said supply roll for free rotation about a fixed axis of rotation while allowing free axial movement of said supply roll along said fixed axis and said control means engages and continuously axially positions said supply roll to provide said controlled unwinding, said control means comprising: carriage means supported for movement substantially radially toward and away from said supply roll, guide means carried by said carriage means and engaging side edge means of said elongated strip during said unwinding, bearing surface means carried by said carriage means and engaging the outer circumference of said supply roll to prevent said supply roll from overrunning, and urging means yieldingly and continuously urging said carriage means toward said supply roll to thereby yieldingly urge said bearing surface means against said outer circumference while simultaneously holding said guide means against said side edge means throughout said unwinding.

8. A device as set forth in claim 7 in which said guide means comprises a pair of freely rotatable rollers supported on said carriage means so as to engage opposite side edges of said elongated strip and said bearing surface means comprises another rotatable roller supported on said carriage means so as to engage the outer circumference of said supply roll.

9. A device as set forth in claim 7 further comprising vertically arranged track means supporting and guiding said carriage means for vertical movement and said carriage means is supported by a plurality of rotatable wheel means arranged to provide a broad stable base so that said carriage means and said guide means will be precisely located relative to said track means.

10. A device as set forth in claim 7 further comprising vertically arranged track means supporting and guiding said carriage means for vertical movement and said urging means comprises spring means acting together with the force of gravity to pull said carriage means toward said supply roll.

11. A device as set forth in claim 7 further comprising vertically arranged track means supporting and guiding said carriage means for vertical movement and said carriage means is supported by a plurality of rotatable wheel means arranged to provide a broad stable base for said carriage means so that said carriage means and said guide means will be precisely located relative to said track means, and in which said guide means comprises a pair of freely rotatable rollers supported on said carriage means so as to engage opposite side edges of said elongated strip and said bearing surface means comprises another rotatable roller supported on said carriage means so as to engage the outer circumference of said supply roll, whereby said broad stable base provided by said wheel means assures said carriage means and rollers carried thereby are always precisely located relative to said track means to thereby correspondingly precisely locate said elongated strip as it is unwound from said supply roll.

12. A device as set forth in claim 11 in which said vertically arranged track means comprises plate means having spaced apart vertically arranged groove means for receiving said wheel means and having vertically arranged elongated opening means extending therethrough, and in which said carriage means comprises, a first carriage having a plurality of rotatable wheel means arranged on one side of said plate means, a second carriage having a plurality of rotatable wheel means arranged on the opposite side of said plate means, and fastening means extending through said elongated opening means and fastening said first and second carriages together to define said carriage means which is freely vertically movable along said elongated opening means, said first and second carriages having their respective wheel means engaging opposite side surface means of said vertical plate means with wheel means of at least one of said carriages being guided by said groove means to provide a precise movement of said guide means and bearing surface means.