US2643698A

US2643698A - Machine for forming continuous wire coils

Info

Publication number: US2643698A
Application number: US138225A
Authority: US
Inventors: David E Crooker
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-01-12
Filing date: 1950-01-12
Publication date: 1953-06-30
Anticipated expiration: 1970-06-30

Description

June 30, 1953 D. E. CROOKER MACHINE FOR FORMING CONTINUOUS WI RE COILS 4 Sheets-Sheet 1 Filed Jan. 12, 1950 INVENTOR.

June 30, 1953 D. E. CROOKER MACHINE FOR FORMING CONTINUOUS WIRE COILS Filed Jan. 12, 1950 I 4 Sheets-Sheet 2 I I ggED/TOR. BY

June 30, 1953 CROOKER' 2,643,698

MACHINE FOR FORMING CONTINUOUS WIRE COILS Filed Jan. 12, 1950 4 Sheets-Sheet 3 WWI gaililivrole. A

June 30, 1953 D. E. CROOKER- MACHINE FOR FORMING CONTINUOUS WIRE CO ILS 4 Sheets-Sheet 4 Filed Jan. 12, 1950 7 4f IEIZQ'INTOR.

Patented June 30, 1953 UNIT so TATE s FATE NT owl-cc FOR FORMING CONTINUOUS V WIRE GOILS David E. Crooker, Ontonagon, lvlich assignor of one-half to Lloyd L. Feike'r, Mar'Shfila, W i-s Applicaition January 12, 1950,=Serial No. 138,225

S'Claiins. (01. 15364") This invention relates to improvements in machines for forming continuous wire coils.

Devices which have been heretofore developed for the formation of continuous wire coils have operated on the principle of using a positive pushing action to feed the uncoiled wire stock against an angular surface. This operation was designed to impart a uniform curvature to the Wire.

'In certain applications, such as in the manufacture of non-skid rubber traction members, it is desirable to employ metal coils which are formed of wire which has been corrugated prior to its being made into coils. The conventional type of wire coiling devices as above referred to are unsatisfactory when handling corrugated Wire due to the high incidence of failure of the wire, either during the forming operation, or soon after the coil is put to use, which failure is caused by the increase in "the amount of bend which is already present in corrugated wire. This increased bend results when the corrugated wire is pushed against the angled surface of the device, the wire tending to -squeeze together somewhat like =an accordion, and thereby causing the corrugations which are already in the wire to be bent to a greater extent. This greatly weakens the wire. Since -a relatively hard steel wire is required for the coil, its tendency toward brittleness increases the possibilities of fracture.

It is therefore ;a general object of the present invention to provide a wire coil forming machine which is capable of forming a continuous coil from either straight -or corrugated stock without danger of seriously weakening or of fracturing the wire.

A further object of the invention is to provide a machine for forming continuous wire coils wherein the uncoiled wi-reis pulled into, rather than-pushed into the machine, thereby eliminating the possibility of increasing the amount of bond in corrugated wire or of undesirably bend= ing a straight wire.

A further object of the invention is to provide a machine of the class described wherein the unforfned wire is formed :into a coil by being pulled "around and held against the periphery of 'a freely rotatable cylindrical mandrel, there being a plurality of driven rollers which are disposed around the periphery of said mandrel in a predetermined anguia'r relationship therewith and which c'oact with the wire.

A further object of the invention is to proride a 'machine of the class described which can be readily adju's'tedto form "coils of various pitch by varying the angularity of the rollers,

2 A further object of the invention is to provide a machine of the class described wherein one convolution only of the wire contacts the mandrel, thereby limiting the sliding contact of said Wire with said mandrel to said one convolution,

' the disposition of the-rollers being such as to engage the formed coil with a compressive rolling contact, and there being substantially no sliding engagement between the formed coil and said rollers. V l

A further object Of-jthe invention is to provide 'a machine of the class described wherein the rollers can be moved axially on their supporting shafts to vary theco'rnpressive forces exerted by said rollers on the coil. a

A further object offthe invention is to provide a machine of the class described, 'w-herein the rollers can readilybesimultaneously swung away from and toward thejnran'drel to permiteasy access to the mandrel'assernblyan'd to said rollers.

A further object of the invention is to provide a machineof the class "described which is strong and durable, efficient in operation, and otherwise welladapted for the purposes described.

With the above and other objects in view, the

invention consists of the improved coil forming a machine; and alloffits part and "combinations, as set forth in the claims, and all equivalents thereof. v

In the drawings accompanying and "forming a part of this specification, wherein the same referonce characters indicate th same parts in all of the views, and wherein is shownone completev embodiment of the preferred form of the invention:

Fig.1 is 'a'pe'rspect'ive ide view of the improved coil rennin-g machine taken from a point forwardiyor and at on "side of the machine;

Fi 2 is a perspective side view of'the machine of'Fig. 1 taken from a point rearwardly of and at the same =side of the machine;

Fig. 3 T is :a perspective front view of, the machine shown in Figs. 1 and 2;

Fig. "4 is a view similar to Fig. '3, but showing th rollersmoved outwardlyfrom the mandrel and with thew-ire coil removed; and

- .Fig. '5 is aview taken approximately alongthe line. 5-5'of 3, with two rollers removed and with-'a port'ion .of the mandrel assembly broken away and shownl'in section. 1

Referring more particularly to the drawing, the numeral 4.0 indicates a base plate on which are fixedly mounted three vertically extending, substantially rectangular bearing plates '11, I2 and ll3. The plate vH is the smallest, and the plates l2 and i3 are successively larger than plate H. The plates ll, |2 and I3 are respectively formed with circular apertures l4, I5 and I9- which vary in siz similarly to the plates in which they are formed. The plates are also formed with slots I8 and I9 which afford communication between said apertures and the upper edges of the respective plates. The plates I2 and |3 are also provided with pairs of upstanding ears 29 fixed thereto adjacent the slots ll, l8 and 9, each of said pairs of ears being provided with a tightening bolt 2|.

Mounted in the circular apertures E4, I5 and I6 respectively, are

circular plates

22, 23 and 24, each of which have substantially the same diam- 22, 23 and 24 are slidable within their respective mounting apertures when the bolts 2| are in loosened condition.

The circular plate 22 is formed with substantially rectangular peripheral notches 25, 25 and 21 which are spaced apart approximately 120. Formed in the bases of the notches 25, 25 and 2'! and extending radially inwardly therefrom are substantially rectangular notches 28, .29 and 39. Mounted in th notches 28, 29 and 39 are spherical or ball and socket bearings, 32 and 33, through which shafts 34, 35 and 36 rotatably project. The bearings 3|, 32 and 33 areheld in place by suitable retaining bars 3'1, 38 and 39 positioned in and fixed to the bases of the notches 25, 2G and 21.

The circular plate 23 i formed with peripheral notches 40, 4| and 42 which are similar to the notches 25, 29 and 21 in the plate 22, and is formed with notches 43, 44 and 45 which are similar to the notches 28, 29 and 39 in the plate 22. Mounted in the notches 43, 44 and 45 are spherical, or ball and socket bearings 46, 4'! and 48 through which the

shafts

34, 35 and 36 also rotatably project. The bearings 46, 41 and 43 are held in place by retaining bars 46'. 41' and 48.

The circular plate 24 is'formed with peripheral notches 49, 59 and 5|. and 52, 53 and 54 which are similar to th notches 49 and 43 respectively in the plate 23. Mounted in the notches of the plate 24 are spherical or balland socket bearings 55, 56 and 51 through which relatively short shafts 58, 59 and 60 rotatably project. The bearings 55, 56 and 51 are held in place by retaining bars 6|, 62 and 63 which are fixedly mounted in the notches 49, 58 and 5|.

Referrin to Fig. 2, it will be noted that sprockets 64. 65 and 66 are fixed to the outer end portions of the shafts 58, 59 and 60. respectively. One of the shafts 58, 59 or 69 may be connected to a suitable source of rotative power. Figs 1 and 2 show a hand crank 6! connected to the shaft 58 for driving purposes. An endless chain 58 circumscribes and drivingly connects all of the sprockets 53, 59 and 60 as shown.

The inner ends of the short shafts 58, 59 and 69 are connected to the adjacent ends of the

shafts

34, 35 and 36 by means of universal joints 69, 19 and H. Keyed ontothe opposite ends of the

shafts

34, 35 and 36 are substantially

cylindrical rollers

12, 13 and 74. The rollers are fixed against rotative movement relative to their shafts, but may be selectively moved axially of said shafts for a purpose to be later described. The rollers 12, 13 and 14 are provided with set screws 12, 13' and I4 respectively for releasably fixing said rollers to their shafts; the set screw 18 fixedly mounted adjacent one end thereof as by set screws 19. The flange of the collar 18 has an annular groove formed in its face and forms part of a thrust bearing which is made up of a plurality of balls 89 mounted in suitable retainers and which includes a second flanged sleeve 8|, the

flange of'which' is also formed with an annular groove. The sleeve 8| has a polygonal shoulder portion 82 and has an elongated portion 83 which is externally threaded and which projects through the bore 15. The sleeve 8| has an axial bore having a diameter substantially equal to that of the mandrel l7.

Threaded on that portion 83 of the sleeve 8| which is on the opposite side of the plate 22 from the shoulder 82 is a nut 84 which secures the sleeve 8| against axial movement. Threaded on the portion '83 of the sleeve 8| adjacent the nut 84 is a sleeve 85 which has a threaded bore 86 and which has an unthreaded bore 87, the diameter of which is substantially the same as the diameter of the mandrel T7. The sleeve 85 has two

portions

88 and 89 of reduced outside diameter, as shown, and the outer end portion of said sleeve is formed with a helical end surface 99. The end surface 99 is spaced axially inwardly from the adjacent end of the mandrel 71.

Mounted on the outer face of the plate U adjacent the aperture l4 therein is an angle bracket 9| having a portion 92 extending toward the mandrel i1. Adjustably mounted on the portion 92 of the bracket 9| is a wire feed guide member 93. The member 93 may consist of a pair of

elongated bars

94 and 95, one of which is formed with a longitudinal rectangular groove 96 in the meeting face thereof (see Figs. 1, 2 and 4). The inner ends of the bars 94 and are preferably tapered as shown in Fig. 4, and said bars are secured to each other by cap screws 91, the guide member 93 being secured to the bracket 9| by cap screws 98 (see Figs. 3 and 4).

Fixed to the outer face of the circular disc 22 are a pair of spaced pins 99 which project outwardly and which are adapted to be engaged by a Wrench [99, the latter being formed with cooperating holes to receive said pins. By loosening the adjustment bolt 21 on the upper edge of the plate H, the circular plate 22 can be rotated from the position of Fig. 3'to the position of Fig. 4. As this is done, the angularity of the

shafts

34, 35 and 36 is changed and the rollers l2, l3 and 14 are moved outwardly, as shown in said figures,

To put the machine into operation, the rollers are moved to the ositions of Fig. 4, and a strand of wire |0| (straight or corrugated) from any suitable source, such as the reel I0 I (see Fig. 2), is fed through the guide member 93. A few con-- volutions of coil I92 are then formed by hand winding the wire around the mandrel 71. With an extent of coil thus formed, the rollers l2, l3

and 14 are then moved into the positions shown in Fig. 3 by manipulating the wrench N10 to rotate the plate 22 in a clockwise direction, as viewed in Figs. 3 and 4. The adjustment bolt 2| is then tightened to prevent rotation of the plate gamma.

Referring to Fig. 5, it will be mited that substantially one convolution only ofthe coil I02 is in contactwith the mandrel 'II. I'he roll'er-s I2, I3 and I4 are'positioned so 'that'the inner peripheral edge portion of each (the edge portion nearest the plate 22) engages the periphery of the convolution of the coil I02 which encircles the mandrel 'and holds said convolution against the mandrel. The angula-rity of the 'rollers I2, 13 and I4 is such that the outer peripheral edge portion thereof (the edge portion farthest rr'om the 'platel are positioned closer "to "the axis of the nr'iandrel 11 than the inner peripheral edge portions. This results in a squeezing of the portion of the coil outwardly of the end of the mandrel between the rollers I2, I3 and Hand creates agri ping action when said rollers are rotated. V

'

Ihe shafts

34, 35 and 38 and the rollers fixed thereto are then simultaneously rotated "in the direction indicated in Figs. 3 and 5 by rotating one of them in a clockwise direction, as viewed in Fig. 2, any suitable means, such *as by the crank 61, being employed. This rotation of the rollers I2, I3 and I4 causes simultaneous'rot'ation of the coil I02 due to the gripping action thereon of the outer peripheral portions of said rollers. Rotation of the coil I02 causes more wire to be drawn in and around the mandrel 'andto be formed into additional convolutions of the 0011 I62. As this additional wire is drawn around the mandrel H, the mandrel rotates in the sleeves BI and 85. p

The rollers I2, '53 and I4 are disposed around the coil I02 approximately 120 apart and at such angularity that the portions of the coil I02 which are in contact with each roller are positioned in "a plane of rotation of said roller. Fig. 5 shows this relationship between the coil I02 and the roller 14 wherein the straight line A-A isal'ined with the portion of one convolution of the coil H12 which is in contact with the roller T4. The line B indicates the plane of rotation of the roller I4 which intersects the point of contact of the roller '54 with the convolution designated. The roller i4 is disposed so that the line A-A is'p'arallel with the plane of rotation B (and all other parallel planes of rotation). The same relationship holds true between the other rollers and the convolutions in engagement therewith. The angularity of the rollers permits a rolling contact of the coil I02 with said rollers and causes said coil to be drawn "outwardly from the mandrel as it is formed, without causing any sliding of the coil across the faces of the rollers. The only sliding contact, other than thato'f the wire passing through the guide 93, is the sliding of the coil longitudinally on the short extent of the mandrel with which the one convolution of said coil is in contact.

This latter sliding contact urges the mandrel Tl axially outwardly toward the rollers, but such movement is prevented by the thrust bearing formed by the sleeves "I8 and ill and the ballsfflfl.

The operation of forming a coil I02 in the above described manner is continuous, as colltrasted with the intermittent operation of prior mandrel type coil forming mac-hi'nes. "In addition, the operation of pulling the wire inane around the mandrel, does not tend to cause any increase in the amount or bend in acorrugated wire which is formed thereby, in cOntr-adistinction to the increased bending which results when a wire is pushed against an angled plate in "forming a coil.

By mounting the shafts '34, 35 and 36 in the manner described and shown, so that they are movable between the positions of Figs. 3 and '4, therollers 12, I3 and M are capable of forming coils fr'om'=wire of various diameters By replacing the mandrel assembly 7'6 with an "assembly in whichth'e mandrel is of different selected diameterrcoils of the new selected diameter can be formed. By changing the rollers I2, I3 and I4 for others offia different selected diameter, a still further range "of coil diameter and wire thickness is =madep'oss'ible.

Movement of the rollers '12, i3 "and 14 axially on their shafts changes the spacing between the axis of the mandrel "I? and the nearest outer .peripheral edge portion of the rollers. Moving the rollers toward the plate 2-2 increases this spacing, and movement away from the :plate decreases this spacing. ,The efiect of such movement "Of the rollers is to increa'seor decrease the squeezing pressure of the rollers on the portion of the coil adjacent the "outer peripheral edges thereof, without effecting the amount'of pressure exerted-o'n theportion of the coil encircling the mandrel H. The adjustment of the amount of squeeze exerted by the rollers makes possible the prevention of slippage between said rollers and tho'coil- I92. I From a comparison of Figs. 3 and 4 it is apparent that movement of the rollers outwardly by rotation of the plate 22 changes the angular relationship of said rollers. -A specific angularity of :the, rollers causes said rollers to urge the portion offthe coil :in engagement therewith in a specific direction, to-th'ereby form 'a coil of a specificqpitch. It is apparent that a variety of coils having various diameters, pitches and wire thickness can be manufactured on the improved machine.

Various other changes and modifications may be made without departingfrom thespirit of the invention, and all of such changes are contemplated as may come with-in the scope of the claims.

Whatl claimis:

1. In a-machine for manufacturing continuous wire coils, a :f-reely rotatable mandrel having an exposed endpor-tion which is adapted to receive an extent-of wire therearound forming one convolution of a coil; a source of supply of wire; a plurality of spaced rollers disposed adjacent said end portion of the mandrel and biased with respect thereto on convergent axes, said rollers being located so that their peripheries engage said coil convolution as well as portions of the coil beyond the end ofthe mandrel; and means for causing simultaneous rotation of said rollers, said rollers being so disposed with respect to said mandrel and coil that when said rollers are rotated the coil and mandrel are rotated to draw wire around the mandrel from said source of supply and to deliver coiled wire longitudinally off of the mandrel end portion, the axially convergent disposition oi said rollers being such that the peripheral portions. of said rollers which are in engagement with portions of the coil beyond the end of the mandrel are positioned closer to the mandrel axis than the portions engaging the coilconvolution on the mandrel, to thereby provide a gripping action on the portionofthe coil beyond the end of the mandrel.

2. In a machine for manufacturing continuous wire coils, a freely rotatable mandrel having an exposed end portion which is adapted to have an extent of wire wound therearound to fo'r'm one convolution of a coil; a source of supply of wire; a plurality of spaced substantially cylindrical rollers disposed adjacent said end portion of the mandrel and biased with respect thereto, said rollers being located so that a portion of each of their peripheries engages said coil convolution and so that another peripheral surface portion of each roller extends beyond the end of the mandrel; and means for causing simultaneous rotation of said rollers, said rollers being so disposed with respect to said mandrel and coil that when said rollers are rotated the coil and mandrel are rotated to draw wire around the mandrel from said source of supply and to deliver coiled wire longitudinally off of the mandrel end portion, the rollers being disposed with a peripheral surface portion beyond the end of the mandrel positioned closer to the mandrel axis than the peripheral surface portion thereof in engagement with the coil convolution on the mandrel, thereby creating a gripping action :of' said rollers on the portion of the coil beyond the end of the mandrel.

3. In a machine for manufacturing continuous coils, a freely rotatable mandrel having an exposed end portion which is adapted to receive an extent of wire therearound forming one convolution of a coil; a source of supply of wire; a plurality of spaced rollers positioned adjacent said end portion of the mandrel with their axes convergent and located so that their peripheries engage said coil convolution as well as portions of the coil beyond the end of said mandrel, said rollers being biased with respect to said mandrel such that the portion of the convolution engaged by a roller extends in a direction substantially parallel to a plane of rotation of said roller; and means for causing simultaneous rotation of said rollers to rotate said coil and mandrel and draw wire around the mandrel from said source of supply and deliver coiled wire longitudinally off of the mandrel end portion, the convergent axial disposition of said rollers being such that the peripheral portions of said rollers in engagement with the portions of the coil beyond the end of the mandrel are positioned closer to the mandrel axis than the portions engaging the coil convolution on the mandrel, to thereby provide a gripping action on the portion of the coil beyond the end of the mandrel.

4. In a machine for manufacturing continuous coils, a freely rotatable mandrel having an exposed end portion which is adapted to have an extent of wire wound therearound to form one convolution of a coil; a source of supply of wire; a plurality of spaced cylindrical rollers positioned adjacent said end portion of the mandrel and located so that a portion of the periphery of each engages said coil convolution and so that another portion of the periphery of each roller extends beyond the end of the mandrel, said rollers being so biased with respect to said mandrel that the portion of the convolution engaged by a roller extends in a direction substantially parallel to a plane of rotation of said roller; and means for causing simultaneous rotation of said rollers to rotate said coil and mandrel to draw wire around the mandrel from said source of supply and to deliver coiled wire longitudinally off of the mandrel end portion, the rollers being disposed with the peripheral surface portions thereof which are beyond the end of the mandrel positioned closer to the mandrel axis than the peripheral surface portions thereof which are in contact with the convolution on the mandrel, thereby creating a 8 gripping action on the portion of the coil beyond the end of the mandrel.

5. In a machine for manufacturingcontinuous wire coils, a freely rotatable mandrel having an exposed end portion which is adapted to receive an extent of wire therearound forming one convolution of a coil; a source of supply of wire; a plurality of spaced substantially cylindrical rollers disposed adjacent said end portion of the mandrel and biased with respect thereto, said rollers being located so that a portion of the periphery of each engages said coil convolution and so that another portion of the periphery of each roller extends beyond the end of the mandrel; a rotatable supporting shaft for each of said rollers, said rollers being mounted on said shafts in a manner to prevent relative rotative movement thereon and to permit selective adjustment of their axial positions i thereon; and means for causing simultaneous rotation of said rollers, said rollers being so disposed with respect to said mandrel and coil that when said rollers are rotated the coil and mandrel are rotated to draw wire around the mandrel from said source of supply and to deliver coiled wire longitudinally off of the mandrel end portion, the rollers being disposed with the peripheral surface portions thereof which are beyond the end of the mandrel positioned closer to the mandrel axis than the peripheral surface portions thereof which are in engagement with the coil convolution on the mandrel, thereby creating a gripping action of said rollers on the portion of the coil beyond the end of the mandrel, said gripping action being selectively controlled by adjustment of the axial positions of said rollers on their supporting shafts.

6. In a machine for manufacturing continuous wire coils, a freely rotatable mandrel having an exposed end portion which is adapted to receive an extent of wire therearound forming one convolution of a coil; a source of supply of wire; a plurality of spaced substantially cylindrical rollers disposed adjacent said end portion of the mandrel, said rollers being located so that a portion of the periphery of each engages said coil convolution and so that another portion of the periphery of each roller extends beyond the end of the mandrel; a rotatable supporting shaft for each of said rollers, said rollers being mounted on said shafts in a manner to prevent relative rotative movement thereon and to permit selec tive adjustment of their axial positions thereon, said rollers being so biased with respect to said mandrel that the portion of the convolution engaged by a roller extends in a direction substantially parallel to a plane of rotation of said roller; and means for causing simultaneous rotation of said rollers, to rotate said coil and mandrel to draw wire around the mandrel from said source of supply and to deliver coiled wire longitudinally oif of the mandrel end portion, the rollers being disposed with the peripheral surface portions thereof which are beyond the end of the mandrel positioned closer to the mandrel axis than the peripheral surface portions thereof which are in engagement with the coil convolution on the mandrel, thereby creating a gripping action of said rollers on the portion of the coil beyond the end of the mandrel, said gripping action being selectively controlled by adjustment of the axial positions of said rollers on their supporting shafts.

7. In a machine for manufacturing continuous wire coils, a mandrel having an exposed end portion which is adapted to have an extent of wire wound therearound to form one convolution of a coil; a source of supply of wire; a plurality 'of spaced rollers disposed adjacent said end portion of the mandrel and biased with respect thereto, said rollers being located so that a portion of each of their peripheries engages said coil convolution and so that another peripheral surface portion of each roller extends beyond the end of the mandrel; and means for causing simultaneous rotation of said rollers, said rollers being so disposed with respect to said mandrel and coil that when said rollers are rotated the coil is rotated to draw wire around the mandrel from said source of supply and to deliver coiled wire longitudinally off of the mandrel end portion, the rollers being disposed with a pcripheral surface portion beyond the end of the mandrel positioned closer to the mandrel axis than the peripheral surface portion thereof in engagement with the coil convolution on the mandrel, thereby creating a grippin action of said rollers on the portion of the coil beyond the end of the mandrel.

8. In a machine for manufacturing continuous wire coils, a mandrel having an exposed end portion which is adapted to receive an extent of wire forming one convolution of a coil; a source of supply of wire; a plurality of spaced rollers disposed adjacent said end portion of the mandrel and biased with respect thereto on convergent axes, said rollers being located so that their peripheries engage said coil convolution as well as portions of the coil beyond the end of the mandrel; and means for causing simultaneous rotation of said rollers, said rollers being so disposed with respect to said mandrel and coil that when said rollers are rotated the coil and mandrel are rotated to draw wire around the mandrel from the source of supply and deliver coiled wire longitudinally off of the mandrel end portion, the axially convergent disposition of said rollers being such that the peripheral portions of the rollers which are in engagement with portions of the coil beyond the end of the mandrel are positioned closer to the mandrel axis than those portions of the rollers which engage the convolution which is still on the mandrel. DAVID E. CROOKER.

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