US2661914A

US2661914A - Tensioning mechanism for winding machines

Info

Publication number: US2661914A
Application number: US31237A
Authority: US
Inventors: Melvin A Thom
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-06-05
Filing date: 1948-06-05
Publication date: 1953-12-08
Anticipated expiration: 1970-12-08

Description

Dec. 8, 1953 M. A. THOM 2,661,914

TENSIONING MECHANISM FOR WINDING MACHINES Filed June 5, 1948 2 Sheets-Sheet l Dec. 8, 1953 M. A. THOM 2,661,914

TENSIONING MECHANISM FOR WINDING MACHINES Filed June 5, 1948 v 2 Sheets-Sheet 2 INVEN TIOR. fizviwflyam Patented Dec. 8, 1953' "YT-,1

renew TENSEONING- MECHANESM FOR WINDING MACHENES Melvin A. Thom, Brighton, N. Y.

Application June 5, 1948, Serial No. 31,237

15 Slaims.

This invention relates to a tensioning mechanism for winding machines, with particular reference to handling fine wire such as employed in winding electrical resistors, and has for its purpose to aiiord a structure that will maintain a substantially constant and uniform tension on winding material such as wire as it is being wound on to a form, and will maintain the wire against movement when the winding operation is interrupted.

A more particular purpose of the invention is to afford a construction in which the winding material or wire passes around a tensioning roll and is gripped by a resilient frictional or ruboer-like periphery on the roll, movement of the tensioning roll being retarded to a varying degree depending upon the tension exerted on the wire by the winding mechanism, thus lessening the retarding of the tensioning roll as the winding pull on the wire increases and increasing the retarding of the tensioning roll as the winding pull on the wire decreases, in order to maintain a varying retarding action on the tensioning roll in accordance with the variations in the pull exerted on the wire at the winding point, and

serving to hold the wire against movement by engagement of the tensioning roll therewith when the winding operation is temporarily dissive changes in tension which are obviated To this invention. a V

A further purpose of the invention is to afford mechanism that will hold a wire or thread stationary during interruption of the winding machine operation as for instance where the winding mechanism is reversed to remove a quantity of wire, thus enabling more successful and efficient winding of electrical resistors requiring close tolerances of from plus or minus one per cent to plus or minus one-tenth of one per cent, owing to maintaining constant, even tension and consequently greater uniformity in the winding of wire on a resistor form.

An additional object of the invention is to enable a wide range of adjustment of the tension exerted on the wire while being wound, and by reason of such wide range and the uniformity of any selected tension, to facilitate manufacturing electrical wire-wound resistors so as to obtain more wire on a given winding form for a given wire size and resistance range, thus increasing the efliciency of the resistor as well as the range of resistors than can be wound when governed with such a tensioning mechanism.

Still a further purpose of the invention is to reduce the tension exerted on the supply reel from which the wire is unwound, controlling the wire by atensioning r011 located between the supply reel and the unwinding point and acting to hold the wire frictionally so as to prevent excessive tension on the supply reel, and by the use of rubber or other rubber-like or resilient frictional peripheral surfaces on positioning and tensioning rolls around which the wire travels, to afford mechanism for handling enamelled wire without damage to the enamel during the winding operation. 7 I

Another object of the invention is to afford a practical mechanism that can readily be arranged to accommodate any size wire, thread, or other winding material, is adaptable to any winding speed, and will afford the required friction between the wire and tensioning roll to prevent slippageo'f the wire thereover.

Any additional purpose of the invention is to afford a mechanism of simple, and practical construction which can be easily and quickly adjusted and controlled for any required size of wire or thread, for any winding speed, and for any required retarding action on the tensioning roll.

To these and other ends, the invention consists in the construction and arrangement of parts that will appear clearly from the following description when read in conjunction with the accompanying drawings, the novel features being pointed outin the claims following the speciii cation.

In the drawings:

Fig. 1 is a view in side elevation showing a mechanism constructed in accordance with a preferred embodiment of the invention and i1- lustrating the position of the control device and brake when there is tension on the winding material at the winding point and the retarding ac- 3 oration, and the retarding action on the tensioning roll is increased;

Fig. 3 is a plan view, and

Fig. 4 is an enlarged detail vertical sectional view on line dl of Fig. 1 looking in the direction indicated.

It is to be understood that the invention may be carriedout in a variety of ways,,being adapt: able to the winding of wire, thread, or any other material that is to be unwound from a supply reel and wound on to a receiving form such as.

a porcelain body in the case of an electrical wirewound resistor, and the structure. shown herein. is intended only as illustrative of one practical embodiment of the invention.

Referring more particularly to the drawings in which like reference numerals refer to the same parts throughout the several views, I designates a suitable base. or support to which is attached the side brackets 2 within which are removably arranged suitable ball bearing assemblies adapted to receive the shaft 3 supporting the supply reel 4 from which the wire 5- or other winding material is unwound, while 3 designates adjusting nuts for securing the supplyreel on the shaft 3. Any suitable conventional means may be employed for slightly retarding movement of the shaft 3 so as to prevent free spinning motion of the supply reel while at the same time permitting proper movement thereof as, the wire is drawn therefrom for winding on to a porcelain resistor body or other form.

The wire 5 after leaving the supply reel 4 travels around a rotatable idler positioning roll i, see Figs; 1 and 3, that" preferably isprovided M ing roll I being mounted on a shaft" 8' that is suitably journalled in the brackets 9' mounted at the sides of the base I.

Referring to Figs. 1 and, 2, the wire 5 travels around the positioning roll I clockwise and as it leaves the positioning roll, it travels-upwardly and rearwardly around a tensioning roll II arranged parallel to the positioning roll and with its longitudinal axis somewhat below that of the positioning roll and in a vertical plane oflset rearwardly from that of the positioning roll. The tensi'onirig ro l is provided with a resilient frictional. periphery of gum rubber or rubber-like material that prevents the wire from slipping thereover, and the wire travels around the ten sioning roll II anti-clockwise, thence upwardly and forwardly to a control device that will presently be described.

The tensioning roll I I is supported by trunnions I2 mounted in. the brackets 9, see Fig. 4,

and in order to impose a retarding or braking action on the tensioning roll II, the trunnions I2 have fixed. thereon at their ends the braking disks I3 which rotate with. the tensioning' roll I! and are permitted to travel. more freely as the tension on the wire atthe Winding. point increasesand less freely as the tension on the wire at the winding point decreases and thus to retard movement of the windingmaterial'.

To effect such retarding of the tensioning roll,

there are provided brake shoes I4 having felt or other frictional surfaces I5 engaging the-braking disks I3. The brake shoes I4 are held against the braking disks by spring arms I6 on which they are mounted and which are fixedly and adjustably secured on the ends; of a spindle I1 which is journalled in the brackets 9 and has an oscillating movement in accordance with the varying tension exerted on the wire at the wind ing .point. Such oscillating movement of the spindle I1 acts to move the spring arms I8 and the brake shoes radially of the braking disks I3, and when the brake shoes are at the outermost points of the braking disks i3, movement ofthe tensioning roll H is; retarded to a maximum degree, whereas when the brake shoes are moved inwardly toward the center of the braking disks I3, retarding of the tensioning roll 8! is: reduced: to permit the correspondingly freer movement of the wire or winding material as the... tension at. the winding point is increased.

The brake shoes are moved radially of the braking; disks; by mechanism that is controlled 'by the, tension on the strand of wire or thread atthe winding point and to this end the brake shoes are operatively connected to a control device that is engaged by the strand of winding material as the latter travels therethrough. To accomplish this, the spindle I! has mounted therein two supporting arms or rods I8 which are adjustable transversely of the spindle I? and carry at their forward ends a mounting I9 on which is pivotally supported a bracket 2| by means of a post 22 permitting the bracket 2! to swivel about the mounting I9 as the position of the strand changes during unwinding from the supply reel 4, and 23 designates. a control pulley mounted in the bracket 2I to receive the strand or wire and to maintain the same in corn trolling relationship to the supporting arms It, while 2t" designates adjacently arranged guide pins between which the strand passes before reaching the control pulley 23, the guide pins 24 being provided with horizontal terminal portions 25 which are suitably fixed to the bracket 2|. After travelling over the control pulley 25, the wire, thread, or other strand passes downwardly under a guide pulley 2S rotatably sup ported in a bracket 21 that is fixed to the base I, and thence the strand passesto the winding pointindicated at 28 where the wire is wound on a porcelain resistor body or other form in tended to receive the strand of winding material by means of any conventional winding apparatus.

The brake shoes are maintained in a normal operative relationship to the braking disks I3 by adjustable spring-controlled means connected to spindle I7, and to effect this, there are provided the rods 29, each of which is secured at one end to the spindle I! and engaged at its opposite end by a coil spring 3 I. The lower ends of the springs 3I are connected to posts 32 which are fixed to an adjustable rock shaft 33 that carries a worm gear 34 fixed thereon, while 35 designates an adjusting worm mounted on a suitable bearing and geared to the worm gear 34 so that by turning the worm 35, the tension on the Springs 3I can be varied to effect a greater or less pullon the rods 29 and thus adjust the position of the spindle IT and the brake shoes for their normal operative relationship when maximum tension is exerted on the strand at the winding point, and also tovary the tension of the springs 3 I- as they actuate the brake shoes outwardly in a radial direction with respect to the braking disks when tension on the strand at the Winding point is decreased.

The operation of the mechanism briefly is as follows: The strand of wire, thread, or other winding material as it is wound on to a form is acorn-14 drawn from th supply reel el over and around the positioning roll 'l in a clockwise direction, thence rearwardly, upwardly, and around the tensioning roll H in an anti-clockwise direction, thence upwardly between the guide fingers 2d and over the control pulley 23 in a clockwise direction, thence downwardly and under the guide pulley in an anti-clockwise direction, and thence upwardly to the winding point 28. When the winding material is being wound on to a form with maximum tension, the pull on the strand holds the control pulley 23, mounting I9, and supporting arms it in a lowered position, as illustrated in Fig. 1, and in such position the brake shoes approach the center of the braking disks and impose a minimum retarding action on the disks, permitting a more free movement of the tensioning roll H. The tensioning roll ll having a gum rubber or other resilient, frictionalsurface engaging the strand of wire or thread efiectively prevents any slippage of the latter over the surface of the tensioning roll so that the strand can travel no faster than the tensioning roll permits, and as the pull or tension exerted on the strand at the winding point decreases, correspondingly less pull is exerted on the control pulley 23, mounting ill, and supportingarins l8, permitting the latter to lift from the position shown in Fig. 1 to the position shown in Fig. 2 dueto the action of the springs 3| which determine the position of the spindle l1 and hralre shoes when tension is released on the strand. As this occurs, the brake shoes move outwardly toward the periphery of the braking disks :3, as illustrated in Fig. 2, and exert a correspondingly greater braking action on the braking disks and thus retard movement of the ten- 7 cloning roll ii so that the strand is preventedfrom travelling beyond the tensioning roll I i any faster than the winding mechanism or tension at the winding point requires. If for-any, reason the winding mechanism is entirely stopped or interrupted for a time, the tensioning roll ll losing held against movement by the brake shoes acting on the braking disks in turn holds the strand or wire against movement around the tensioning roll and prevents excessive slack in the strand between the tensioning roll and the Winding point. The unwinding movement of the supply reel is retarded sufficiently to prevent removal of the strand therefrom at a faster speed than it travels around the tensioning roll and the action of the tensioning roll in combination with the ositioning roll "5, and their relation to each other, serves to hold the strand against movement or slack when the winding operation is interrupted, also to maintain a normally constant and uniform tension on the strand at all times during the winding operation. As the strand is unwound from the supply reel 4 at different points endwise of th latter, such variable position of the strand is compensated for by the control pulley and racket 2i swiveling in a 7 horizontal plane about the mounting it so that cover such modifications and departures as may and the scope of the following claims.

I claim: r l l. Tensioning mechanism comprising a supply reelfor windingmaterial, a rotatable tensioning r011 having a frictional peripheral surface around which winding material passes as it is unwound from said supply reel, retarding means comprising a braking disk secured to the tensioning roll to rotate therewith and having a braking face in a plane at right angles to the axis 'of said tensioning roll, abrake shoe engaging the braking face of said disk and movable radially of said axis to vary the retarding action on the tensioning roll a control device connected to the brake shoe acting to eflect said radial movement, said control device including an element engaged by thewinding material andmovable thereby in one direction to move the brake shoe radially toward axis to decrease the retarding action on the tensioning roll, and spring means actuating the brake shoe in the opposite direction to increase the retarding action on the tensioning roll.

Tensioning mechanism comprising a rotatable tensioning roll having a resilient, frictional peripheral surface around which winding material passes, retarding means comprising a braking disk connected to the tensioning roll, a brake shoe engaging said disk and movable, radially thereof to vary the retarding action on the tensioning roll, a control device connected to the brake shoe acting to efiect said radial movement, said control device including an element engaged by the winding material and movable thereby in one direction to decrease th retarding action on, the tensioning roll, and spring means actuating the brake shoe in the opposite direction to increase the retarding action on the tensioning roll.

3. Tensionlng mechanism comprising a rotatable positioning roll, a rotatable tensioning roll arranged-parallel to'the positioning roll and having a friction periphery around'which winding material passes after leaving the positioning roll, retarding means comprising a braking disk connected to the tensioning roll, a brake shoe engaging said disk and movable radially thereof to vary the retarding action on the tensioning roll, a control device connected to the brake shoe acting to efiect said radial movement, said control device including an element engaged by th winding material and movable thereby in one direction to decrease the retarding action on the tensioning roll, and spring means connected to and actuating the brake shoe the opposite direction to increase'the retarding action on the tensioning roll.

4, Tensioning mechanism comprising a rotatable positioning roll, a rotatable tensioning roll arranged parallel to the positioning roll and having a resilient friction periphery with its longitudinal axis located below that or" the posi- I tioning roll and in a vertical plane offsetto that of. the positioning roll whereby winding material passing around the positioning roll travels thence upwardly and rearwardly before going around the tensioning roll, retarding means comprising a braking disk connected to the tensioningrcll, a brake shoe engaging said disk and movable radially thereof to vary the retarding action on the tensioning roll, a control device connected to the brake shoe and acting to effect said radial movement, said control device including an element engaged by the winding material and movable thereby downwardly to decrease the retard- '5"- ing action o the tensionins ro l, and spring means actuating the, brake shoe oppositelyto increase the retarding action on the tensioning roll.

5. Ten ioning mechanism comprising a rotat able, positioning roll, having a resilient friction periphery around which Winding material travels, a rotatable tensioning roll arranged parallel, and in juxtarelation to the positioning roll, thev tensioning roll having a resilient friction periphery with its longitudinal axis located below that of the positioning roll and in a vertical plane offset to that of the positioning roll whereby the winding material passing around the positioning roll travels thence upwardly and rearwardly be-. fore going around the tensioning roll, retarding means operatively associated with the tensioning roll and movable in relation thereto to vary the retarding action, a control device operatively connected to the retarding means and movable as the tension on the winding material varies, the control device being located somewhat above said tensioning roll and including a controlpulley over which the winding material passes after leaving the tensioning roll, and a guide pulley located below and in advance of the control pulley and under which the winding material passes after leaving the control pulley.

6. Tensioning mechanism comprising a rotatable positioning roll and a rotatable tensioning roll arranged parallel thereto, the positioning and tensioning rolls having rubber-like friction peripheries around which winding material passes successively, retarding means comprising a braking disk connected to the tensioning roll, a, brake shoe engaging said disk and movable radially thereof to vary the retarding action on the tensioning roll, a control device connected to the brake shoe acting to effect said radial movement, said control device including an element engaged by the winding material and movable thereby in one direction to decrease the retarding action on the tensioning roll, and spring means actuating the brake shoe in the opposite direction to increase the retarding action on' the tensioning roll.

7. Ifensioning mechanism comprising a rotatable positioning roll and a rotatable tensioning roll arranged parallel to the positioning roll with its longitudinal axis located below that of the positioning roll and in a vertical plane, ofiset to that of the positioning roll whereby winding material passing around the positioning roll travels thence upwardly and rearwardly before going around the tensioning roll, said positioning and tensioning rolls having rubber-like friction peripheries around which the winding material travels successively, retarding means comprising a braking disk connected to the tension,- ing roll, a brake shoe engaging said disk and moving radially thereof to vary the retarding action on the tensioning roll, a control device connected to the brake shoe and acting, to effect said radial movement, said control device includin an lement encas d by h W nd ng material and movable thereby in one direction to decrease the retarding action on the tensioning roll, and spring means actuating the brake shoe in. the opposite direction to increase the retarding action on the tensioning roll.

8. Tensioning mechanism comprising a rotatable positioning roll and a rotatable tensioning roll arranged parallel and in juxtarelation to the positioning roll with its longitudinal, axis below that of the positioning roll and in a ver-.

tical. p ne offset to, that Q 1 he posit on ng. oll wher by he. windi g m t r al. passing a ound the positionin roll traye s enc upward and rearward y before goin around th t nsi n e roll, th p sition and t ns n ne r l havin ru ber-like iri ti nr periphe s aro w i h the windin materia r v ls succ y r a din mea s. c mpris ng a braking i k c ted to the te sicn ng o l, a rake. ho nga in said disk. and moving radia y h re f. to ary t e retard g act n. o the cnsion ne r ll, a coniOl dev ce. QQIHlQQ d Q he brake 1 n tg t e ect. said radial mov m nt, s d ntr devic including an elem nt ne e dby the w n ng; mater al d mov bl t e y n, ne dir tion to decrease the retardin ac on e t nsionine roll, and hi m tu t the rals s oe in the opposite, directionto i r a the. retard n actio on. t ing roll.

9., Iensioning mechanism comprising a rotata l t nsi nine roll h ving a fr o p r ph ry round wh chwin ins m te ia rav r in means comprising a braking disk connected to the. tensioning roll, a brake shoe engaging said braking dish and movable radially thereof, an oscillatory spindle on which said brake shoe is mounted, a control device including supporting arms extending through said oscillatory spindle, rods carried by said spindle, a spring connected to each of, said rods at one end and to an adjustable stationary post at its opposite end, a mounting carried by the opposite ends of said supporting arms, a bracket secured to said mounting, and rotatable means carried by the bracket and engaged by the winding material after it leaves the tenslonine roll.

10. Tensioning mechanism comprising, a rotatable tensioning roll having a friction periphery around which winding material travels, retarding means comprising a braking disk connected to the. tensioning roll, a brake shoe engaging said braking disk and movable radially thereof, an oscillatory spindle on which said brake shoe is mounted, a control device includ ing supporting arms extending through said oscillatory spindle, rods carried by said spindle, a spring connected to each of said rods at one end, and to a stationary post at, its opposite end, a mounting carried by the opposite ends of said supporting arms, a bracket rotatably supported on said mounting for swiveling movement in a generally horizontal plane, a control pulley carried by said bracket for guiding the winding material thereover, guiding fingers attached to the bracket and located in advance of said control pulley, and a guide pulley mounted in a stationary bracket located beneath said control pulley.

ll. Tensioning mechanism comprising a rotatable tensioning roll having a friction periphery around which winding material travels, retarding means comprising a braking disk connected to the tensioning roll, a brake shoe engaging said braking disk and movable radially thereof, an oscillatory spindle on which said brake shoe is mounted, a control device including supporting arms adjustable on said osciilatoryspindle, rods carried by said spindle, a spring connected to each of said rods at one end and to a post at its opposite end, a rock shaft on which said posts are mounted, a worm gear on said shaft, an adjusting worm connected to said worm gear, a mounting carried by the opposite ends, of said. supporting arms, a bracket r0 tatably supported on said mounting for swiveling movement in a generally horizontal plane, a control pulley carried by said bracket for guiding the winding material thereover, guiding fingers attached to the bracket and located in advance of said control pulley, and a guide pulley mounted in a stationary bracket located beneath said control pulley.

12. Tensioning mechanism comprising a rotatable positioning roll and a rotatable tensioning roll arranged parallel and in juxtarelation to the positioning roll with its longitudinal axis below that of the positioning roll and in a ver' tical plane offset to that of the positioning roll whereby the winding material passing around the positioning roll travels thence upwardly and rearwardly before going around the tensioning roll, the positioning and tensioning rolls hav ing rubber-like friction peripheries around which the Winding material travels successively, retarding means comprising a braking disk connected to the tensioning roll, a brake shoe engaging said disk and moving radially thereof to vary the retarding action on the tensioning roll, an oscillatory spindle on which said brake shoe is mounted, a control device including supporting arms adjustable on said oscillatory spindle, rods carried by said spindle, a spring connected to each of said rods at one end and to an adjustable post at the other. end, a mounting carried by the opposite ends of said supporting arms, a bracket rotatably supported on said mounting for swiveling movement in a generally horizontal plane, a control pulley carried by said bracket for guiding the winding material thereover, guiding fingers attached to the bracket and located in advance of said control pulley, and a guide pulley mounted in a stationary bracket located beneath said control pulley.

13. Tensioning mechanism comprising a rotatable tensioning roll around the periphery of which winding material travels, retarding means comprising a braking disk connected to the tensioning roll and having a braking face in a plane at right angles to the axis of said tensioning roll, a brake shoe engaging the braking face of said disc and movable across said face radially of the axis of said tensioning roll, a spindle oscillatable about an axis parallel to the axis of said tensioning roll, an arm rigidly connecting the brake shoe to the spindle so that the posi tion of the brake shoe across the face of the disc is varied on movement of the spindle, means for constantly urging said spindle in a direction to move the brake shoe radially away from the axis of the braking disc, and means for moving the spindle in the opposite direction about its axis comprising a supporting arm secured to the spindle, a bracket mounted for swiveling movement on the free end of said supporting arm, and a roll journaled in said bracket over which the winding material passes after it leaves the tensioning roll, said second named roll being mounted in said bracket for rotation about an axis at right angles to the axis 01' swivel of said bracket.

tatable tensioning roll having a frictional peripheral surface around which winding material travels, retarding means comprising a braking disk connected to said tensioning roll to rotate therewith and having a braking face in a plane at right angles to the axis of said tensioning roll, a brake shoe engaging said braking face and movable radially thereof, an oscillatory spindle on which said brake shoe is carried, said spindle being mounted for rocking movement about an axis parallel to the axis of the tensioning roll, a control device including two rods secured to said spindle and projecting from opposite sides thereof, a spring connected to the free end of one rod and adapted to constantly urge said brake shoe radially away from the axis of said tensioning roll, a mounting carried at the free end of the other rod, a bracket swivelly mounted in said mounting, and a, pulley rotatably mounted in said bracket for rotation about an axis at right angles to the axis of swivel of-said bracket and engaged by the winding material after it leaves the tensioning roll.

15. Tensioning mechanism comprising a rotatable tensioning roll having a frictional peripheral surface around which winding material travels, retarding means comprising a braking disk connected to said tensioning roll to rotate therewith and having a braking face in a plane at right angles to the axis of said tensioning roll, an oscillatory spindle mounted to 'rock about an axis parallel to the axis of said tensioning roll, a flexible arm secured at one end to said spindle, a brake shoe carried at the other end of said arm and engaging the braking face of said braking disk, said arm being flexed to press said brake shoe resiliently against said braking face, a pair of rods secured to said spindle and projecting from opposite sides thereof, a spring connected to the free end of one rod and adapted to constantly urge said spindle in one direction about its axis to move said brake shoe radially across said braking face away from the axis of said tensioning roll, a bracket swivelly mounted on the free end of the other rod, and

g a pulley rotatably mounted in said bracket for rotation about an axis at right angles to the axis of swivel of said bracket and engaged by the winding material after it leaves said tensioning roll.

MELVIN A. THOM.

References Cited in the file of this patent UNITED STATES PATENTS