US1942113A

US1942113A - Coil winding mandrel

Info

Publication number: US1942113A
Application number: US412050A
Authority: US
Inventors: John G Meyers
Original assignee: General Cable Corp
Current assignee: General Cable Corp
Priority date: 1929-12-06
Filing date: 1929-12-06
Publication date: 1934-01-02
Anticipated expiration: 1951-01-02

Description

Jan. 2, 1934. J. G. MEYERS con WINDING MANDREL Filed Dec. 6, 1929 2 Sheets-Sheet l Jam-2, 1934- J MEYERS 1,942,113

COIL WINDING MANDREL Filed Dec. 6, 1929 2 Sheets-Sheet 2 Patented Jan. 2, 1934;

use

COIL WINDING DIANDREL John G. Meyers, Rome, N. Y., assignor to General Cable Corporation, New York, N. Y., a corporation of New Jersey Application December 6,1929. Serial No. 412,050

6 Claims.

This invention relates generally toapparatus for winding coils of wire, and more particularly to an expansible and collapsible mandrel for making layer wound coils.

It is an object of this invention to provide an improved mandrel for winding layer wound coils of the type in which the turns of the first layer are positioned according to a predetermined plan, and the turns of succeeding layers lie, except for short distances at points of cross-over, in the grooves between the turns of the immediately preceding layer. Other objects and advantages of the invention will appear hereinafter.

An illustrative embodiment of the invention selected merely for descriptive purposes is shown in the accompanying drawings, in which:

Fig. 1 is an end view of a mandrel;

Fig. 2 is a side view of the mandrel, partly broken away to show a section substantially on line 22 of Fig. 1;

Fig. 3 is a view similar to Fig. 2, but with the mandrel rotated 96, about its longitudinal axis, the view being a section substantially on line 33 of Fig. 4; and

Figs. 4 to 6 are sections on the correspondingly numbered lines on Fig. 3.

In winding multiplelayer coils in which the layers are not spaced from each other, as by means of sheets of insulating material, it will be apparent that for a coil having a fixed number of turns of a given size and kind of wire the cross-sectional area of the coil wall transverse to the direction of the coil turns may be reduced to a minimum only when the space between adjacent coil turns is reduced to a minimum.

In winding coils of round wire, the space be tween coil turns may be reduced to a minimum only when each of the coil is wound accurately in accordance with a predetermined plan utilizing the available space to the best advantage. Preferably, the turns of the first coil layer lie, except for short distances at the points of cross-over between turns, in planes perpendicular to the longitudinal axis of the coil, and are spaced from wire center to wire center a distance slightly greater than the maximum wire diameter. The turns of the succeeding layers lie, except for short distances at the points of cross-over in the grooves between the turns of the preceding layer. Such a coil will have smaller overall dimensions than a coil of the same number of turns and kind of wire wound in some other manner, and consequently will require less wire for a given number of turns.

Referring to the drawings, andparticularly to Figs. 2 and 3, a spindle 11 is provided at one end with means such as the screwthreaded portion 12, whereby the spindle may be detachably secured by its end to a rotatable shaft, (not shown) conveniently that of a coil winding machine, or an electric motor. Adjacent the screwthreaded portion 12 the spindle 11 is enlarged to form a. collar 13, and abutting the collar 13 is a head flange 16 which may be slipped into place over the screwthreaded end 14 of the spindle. The head flange has on its face toward the end 14 of the spindle a frusto-conical shaped collar 18, the purpose of which will become apparent hereinafter. The head flange 16 also has a plurality of radially extending slots 19, for example four slots spaced equally about the flange. These slots 19 extend from the circumferential edge of the head flange inwardly substantially to the outer surface of the core upon which the coil is to be wound, and their function will appear hereinafter. Thelhead flange preferably is secured against longitudinal movement along, and turning movement about the spindle in any suitable manner, as by means of a pin 1'7.

Referring particularly to Fig. 2, the head flange 16 has a plurality of circumferentially spaced guide pins 20 projecting from its face away from the collar 13, each pin lying substantially parallel to the inclined surface of the collar 18. These guide pins, of which in the embodiment disclosed there are two diametrically spaced from each other, may be secured in the flange in any suitable manner, conveniently by frictional engagement, and preferably extend through and project beyond the other face of the head flange, whereby they may be adjusted longitudinally. Each pin 20 slidably engages an opening 21 in one end of a corresponding core member 22, the core members collectively forming a support or core upon which a coil may be wound.

In the particular embodiment disclosed there are two arcuate shaped core members 22 forming a substantially cylindrical core for winding round coils. When the ends of the core members are in contact with the head flange 16, adjacent longitudinal edges of the core members are separated by relatively narrow gaps, thereby permitting radial movement of the core members inwardly to collapse the mandrel as hereinafter described. The ends of the core members adjacent the head flange 16 have their inner sur-- faces tapered to bear on the frusto-conical shaped collar 18. The core members are movable longitudinally, and because of the operative connection with the inclined pins 20 have concurrently a radial movement. Conveniently the pins 20 are so adjusted that when the core members 22 are moved longitudinally and inwardly, as the mandrel is being collapsed, until they contact with the spindle 11, the pins 20 still. engage the openings 21 to retain the parts in assembled relation.

The ends of the core members 22 distant from the head flange 16 conveniently are provided with means normally tending to draw the core members together, for example, circumferentially aligned recesses 23 retaining an annular spring 24, for example a spiral tension spring with its ends connected together. The inner surfaces of the ends of the core members are tapered similarly to the ends adjacent the head flange 16 for slidably engaging a frusto-conical shaped collar 25 on the inner face of a tail flange 26. The tail flange 26 may be slipped on to the spindle 11 over the screw-threaded portion 14; and

has a plurality of radially extending slots; 32, similar to, andan ularly aligned. with the slots- 19. in the head flange 16,. Relative rotation be: tween the tail flange and the spindle 11 may be prevented by meanssuch as apin 30;,secured in the spindle ll for engaginganarrow. slot or keyway 15 in the, inner edge of the tail flange,

Suitable means. are provided for forcing the tail flange 26, againstthe ends of the core members, and the core members against, the head flange to expand the mandrel, and for main taining the mandrelin expanded condition, during the. winding operation. Merely by wayof example in the embodiment disclosed, a nut 27 engages the screwthreaded end i l. of the spindle 1'1, and may be screwed into place to force the tail flange26against the ends'of thev core members, at the same time moving the-core'members longitudinally. toward the flange 16, andradially outward due to the engagement of the collars 18- and 25with the tapered ends of the core men bers. erably is multiple. and coarse. As the nut 2'7'is unscrewed, the. core members are permitted to move. longitudinally and radially. inward under the. influence of: the spring 24.

Conveniently, the nut 27 isrotatably secured on the'outer face of the tail flange 26, as by means ofa. split plate 33 engaging a circumferential groove 34in thehub of the nut, the plate 33 being secured on the. outer face ofthe flange by screws. Thus it will be seen thatthe core members 22'form anexpansible and collapsible coil winding support or core from which coils readily may be removed by removing the nut27' and the tail flange 26.

In order to insure contact of the core members 22 with the frusto-conical hub 25 on the tail flange when the mandrel is expanded, it may be desirable to-providethe tail flange with means such as the positioning pins 28'for engaging the recesses in the ends of the core members 22'when the tail flange is forced against the ends of the core members to force the ends of the core members against the hub 25.

The core members 22 are provided on their outer surfaces with ridges for positively positioning and holding the turns of the first coil layer in accordance with a predetermined plan.

Preferably the wire positioning ridges are formed by grooving the outer surfaces of the core mem bers in a plurality of substantially equally-spaced parallel grooves lying in planes perpendicular to the longitudinal axis of the mandrel, the spac- For speed inoperation the thread pref ing of said grooves from root center to root center being substantially equal to, and preferably slightly greater than the maximum overall wire diameter, the grooves of the various core members being circumferentially aligned when the mandrel is expanded preparatory to winding a coil. In practice there are slight variations in wire diameter, even in short lengths of wire, and for this reason it is desirable to make the spacing of the grooves slightly greater than the maximum wire diameter, for example 1 to 2 greater.

The winding core has one or more narrow recessed Zones. from which the wire-positioning ridges have been removed extending longitudinally therealong. In the embodiment disclosed, eachof thetwo members 22 has such a narrow recessed Zone 29 extending along each of its longitudinal edges. These narrow recessed zones prevent; the wire-positioning ridges from interfering with the turns of the inner layer when a coil is moved ofi'jfrom the-collapsed-mandrel.

The; operation of winding acoil, on the. mandrel nowwill be described; The mandrel is secured by means of the screwthreadedportion 12. to a rotatable, shaft, conveniently the-winding shaft of: acoil winding; machine, The mandrel is assembled, the nut27beingscrewed uptight on the-end: 14 of the spindle. 1 l to-expand the wire receiving core, to its maximum dimensionsandto move the head; and. tail flanges againsttheends of; the core members 22.,

The endof the wire is secured, ,forexample-t0 aclip'3l on the outer face ofithe-tail flange, conveniently integral with the split plate 33, whence it passes through oneof theslots 32 into-theflrst circumferential groove, of the wire receiving core. The mandrel is then rotated,v suitable tension being maintained on the wire,- and upon the substantial completion of one full turn the-wire by reason of the-tension exerted on it and its riding up on the first part of the-turn,,is movedlongitudinally alongthe mandrel-a distance substantiallyequal tothe diameter of the wire, and is drawn down intothe next. circumferential groove. rotation of the mandrel.

If the distance between the mandrel and the wire supply or wire guide is not too short relative to the length of the coil to be wound, the wire will move automatically from one groove to the next groove when the wire engages the first part of the turn, and no additional means will be required for causing the wire to move longitudinally along the mandrel. In other cases it may be found desirable to provide a suitable traversing wire guide moving back and forth parallel to the rotating mandrel to insure the d sired laying on of the wire in the grooves.

This action is repeated upon further When the last complete circumferential groove on the mandrel core has been filled, the wire will rideup on the top of the first coil layer, and, under tension, will fall into a groove between either the last turn of the first layer and the head flange, or in the groove between the last two turns of the first layer. The course taken here by the wire is dependent upon whether the last groove on the wire receiving core brings the last turn of the first layer one half a wire diameter distant from the head'flange, or flush against the head flange. If the last groove of the wire-receiving mandrel core is a full groove, the even numbered layers of the coil will each have one less turn than the odd numbered layers, while if the last groove of the core is a half groove each coil layer will have the same number of turns.

In the embodiment shown the last groove is a half groove. Upon further rotation of the mandrel the second and following co-il layers are wound as was the first, the turns of the preceding layers serving as the wire positioning ridges.

When the desired number of turns have been wound on the mandrel, rotation is stopped, the wire is severed, and the coil end is secured in any suitable manner to prevent unwinding of the coil. U-shaped clamping members then are positioned on the coil, the legs of the clamping members engaging the ends of the coil through the

slots

19 and 32, and the nut 27 is unscrewed.

The inner end of the coil wire may be loosened from the clip 31 before the nut 2'7 is unscrewed, but preferably the nut is at least partially unscrewed before the wire is detached from the clip 31 in order that as the nut is unscrewed, the coil and the core members 22 will be moved 1ongitudinally of the mandrel with the tail flange 26 to aid in collapsing the mandrel, the core members 22 also moving radially inward under the influence of the spring 24 and the guide pins 20 as they are moved longitudinally. When the nut is loosened, the turns of the coil expand slightly, this expansion being limited by the clamping members. The coil with its attached clamping members may then be slipped oif of the coilforming core, either with or subsequent to the removal of the tail flange and nut 27, the core members 22 moving toward each other to collapse the mandrel and withdraw the wire-positioning ridges from engagement with the inner layer of the coil. The coil then may be tied and finished in the usual manner.

It will be seen that this invention provides a mandrel which is simple in construction and operation, and which is adapted to wind accurately and at high speed layer wound coils having minimum overall dimensions.

It will be understood that the invention may be variously modified and embodied within the scope of the claims.

I claim:

1. An expansible and collapsible coil winding mandrel comprising, in combination, two arouate-shaped sectional members forming a substantially cylindrical mandrel core, each of said sectional members having on its outer surface a plurality of wire-positioning ridges, the ridges of the two members being circumferentially aligned, and lying in equally-spaced parallel planes perpendicular to the longitudinal axis of the core, a narrow zone from which the ridges have been removed extending longitudinally along each edge of each of the sectional members to permit removal of a completed coil from the mandrel when in collapsed condition, end flanges for said core, and means on said end flanges for forcing the sectional members apart to expand the mandrel core as the end flanges are pressed against the ends of the core.

2. An expansible and collapsible coil winding mandrel comprising, in combination, a longitudinally split cylindrical mandrel core, the outer cylindrical surface of said core being grooved with circumferentially aligned wire-receiving grooves lying in planes perpendicular to the axis of the core, a narrow zone from which the ridges between the grooves have been removed extending along each longitudinal edge of each section of the core to expedite removal of a coil from the mandrelwhen in collapsed condition, end flanges for said core, and means for moving the two halves of the core apart to expand the mandrel.

3. An expansible and collapsible coil winding mandrel comprising, in combination, a plurality of sectional members forming a mandrel core, an end flange for said core, a plurality of guide pins extending from the inner face of said end flange and slidably engaging openings in the ends of said sectional members, the arrangement of the guide pins being such that movement of the sectional members toward and away from the end flange is accompanied by radial movement of the sectional members outwardly apart and inwardly together, means normally tending to move said sectional members radially inward to collapse the mandrel, a second end flange, means on the inner face of said second-mentioned end flange for forcing the sectional members radially outward when the end flange is pressed against the end of the core, and means for pressing said second-mentioned end flange against the end of the core to expand the mandrel.

4. An expansible and collapsible coil winding mandrel comprising, in combination, a plurality of sectional members forming a mandrel core, an end flange for said core, a plurality of guide pins extending from the inner face of said end flange and slidably engaging openings in the ends of said sectional members, the arrangement of the guide pins being such that movement of the sectional members toward and away from the end flange is accompanied by radial movement of the sectional members outwardly from each other and inwardly toward each other, a second end flange, and means for pressing said second-mentioned end flange against the end of the core to expand the mandrel.

5. An expansible and collapsible coil winding mandrel comprising, in combination, a plurality of sectional members forming a mandrel core, end flanges for said core, a plurality of guide pins extending from the inner face of one of said end flanges and slidably engaging openings in the ends of the being inclined inwardly toward the longitudinal axis of the core, and means for pressing the flanges against the ends of the core to expand the mandrel.

6. An expansible and collapsible coil winding mandrel comprising, in combination, a plurality of arcuate-shaped sectional members forming a mandrel core having on an end face acircumferentially extending groove, an annular spring lying in the said groove and normally tending to draw the members together to collapse the mandrel, wire positioning ridges on the outer surfaces of said sectional members, end flanges for said core, and means on said end flanges for forcing the core members apart to expand the mandrel.

JOHN G. MEYERS.

core members, said pins