US2962235A

US2962235A - Toroidal winding machine

Info

Publication number: US2962235A
Application number: US646422A
Authority: US
Inventors: Ridler Desmond Sydney; Armsby Bernard Frank
Original assignee: International Standard Electric Corp
Current assignee: International Standard Electric Corp
Priority date: 1956-03-23
Filing date: 1957-03-15
Publication date: 1960-11-29
Anticipated expiration: 1977-11-29

Description

Nov. 29, 1960 Filed March 15, 1957 D. S. RIDLER EI'AL TOROIDAL WINDING MACHINE 8 Sheets-Sheet 1 Inventor D.S.RlDLER- By BE RMS Y Attorney Nov. 29, 1960 D. s. RIDLER ETAL 2,962,235

TOROIDAL WINDING MACHINE Filed March 15, 1957 8 Sheets-Sheet 2 I r "H In venlor -D.S.RIDL ER BEARMSBY BYMWM A ltorney Nov. 29, 1960 D. S. RIDLER EI'AL TOROIDAL WINDING MACHINE 8 Sheets-Sheet 3 Filed March 15, 1957 Inventor DSR IDLER BEARMS BY A Horn 2 y Nov. 29, 1960 D. s. RIDLER ETAL TOROIDAL WINDING MACHINE s Sheets-Shet 4 Filed March 15, 1957 kw 2 WQV 3 4 2 3 4 5 C C C M I m M M N I G a c a l s s 2 M 5 ST W Mm E v Inventor DSRIDLER BEARMSBY A Horn e y Nov. 29, 1960 D. s. RIDLER ETAL 2,962,235

TOROIDAL WINDING MACHINE Filed March 15, 1957 8 sheets-sheet s In venlor DSRIDLER BEARMSBY A llorney Nov. 29, 1960 D. s. RIDLER ETAL 2,962,235

TOROIDAL WINDING MACHINE Filed March 15, 1957 8 Sheets-Sheet 6 Inventor DSRKDLER BEARMSBY Attorney 1 x Nov. 29, 1960 D. s. RIDLER EIAL TOROIDAL WINDING MACHINE Filed March 15, 1957 8 Sheets-Sheet a A ttorn e y United States PatentO TOROIDAL WINDING MACHINE Desmond Sydney Ridler and Bernard Frank Armsby, London, England, assignors to International Standard Electric Corporation, New York, N.Y., a corporation of New York Filed Mar. 15, 1957, Ser. No. 646,422

Claims priority, application Great Britain Mar. 23, 1956 5 Claims. (Cl. 2424) at intermediate points in its length and repeatedly transported in loop form around a portion of said toroid to form successive turns of a winding.

According to another feature of the invention there is provided toroidal winding machines comprising a toroid holder, a wire-positioning device on one side of the toroid position for locating a length of wire, a wire-end anchoring device on the other side of said toroid position to anchor the end of a piece of wire which has been threaded through the torid from said wire-positioning device, a wire transporting device arranged to revolve about a toroid so as to engage a wire between the toroid and said wire-positioning device and to transport a loop of said wire around the toroid to the same side of the toroid position as said anchoring device, and means for engaging with said loop of wire on the anchor side of the toroid position, for Withdrawing said loop through a toroid, and for entering the wire into said wire-positioning device in position for further engagement by said wire transporting means.

Two embodiments of the invention will now be described with reference to the accompanying drawings, in which:

Figs. la-d are schematic plan views of a toroidal winding machine having a linear wire chamber, and show successive stages in the operation of winding one turn of Wire around a toroid,

Figs. 2a-d are corresponding side views of the winding machine of Fig. 1,

Fig. 3 is a plan view of a toroidal winding machine having a circular wire chamber,

Fig. 4 is a side view of the winding machine of Fig. 3.

Fig. 4A shows the general arrangement of a machine for automatically performing the functions of applying successive turns of wire onto a toroid in accordance with the principles outlined in the first embodiment.

Fig. 5 shows a circuit diagram of the driving and sequence control equipment of the machine illustrated in Fig. 4a.

Figs. 6A and 6B show various stages of the wire hooking operation.

Fig. 7 shows the general arrangement of a machine for automatically performing the functions of applying successive turns of wire on to a toroid in accordance with the principles outlined in the second embodiment.

Fig. 8 shows a circuit diagram of the driving and sequence control equipment of the machine illustrated in size of toroids.

reduction gears

20, 21 and 22 and supported on rollers 2,962,235 Patented Nov 29, 19cc ICC wire application cycles.

Referring to Figs. 1a to 1d and 2a to 2d, the machine comprises a wire-positioning device such as a wire chamberl, a hook 2, and a wire transporting device such as a pulley 3. The wire chamber 1 has friction pads 4 at one end through which passes a wire 5.

As shown in Figs. la and 2a, one end of the wire 5 to be Wound on the toroid 6 is threaded through the toroid and anchored in a wire anchoring device .7. The pulley 3, which need not be free to revolve on its own axis, rotates about the toroid 6 bringing a loop of the wire 5 around the outside of the toroid from the left hand to the right hand side, Figs. 1b and 2b. The hook 2 then advances above the wire chamber 1 (Figs. lb and 2b) to avoid interference with the wire 5 therein, and passes through the centre of the toroid 6 to engage the portion of the wire 5 around the pulley 3, Figs. 1c and 2c.

The hook 2 may be caused to engage the portion of the wire 5 on the pulley 3 by an upward movement of the hook 2, or alternatively the portion of the wire 5 may be engaged with the hook 2 by movement of the pulley 3. Clearly a number of methods are possible, but it is desirable to keep any displacement of the book 2 to a minimum in order to be able to. wind the smallest The hook 2 then withdraws the wire 5 into the wire chamber 1 until the wire 5 slips oh? the book 2 at some and. 2d. The tension of the wire 5 when it slipsoff the hook 2 is maintained by the pads 4. Prior to this, the natural bending of the wire 5 around the book 2 provides an adequate tension, which may be adjusted by altering the radius of curvature.

In this manner one turn is wound onthe toroid 6, and for each further turn, the cycle is repeated. Any type of winding may be eifected by providing means for suitably rotating or reciprocating the toroid during winding.

It will be noted that the hook 2 moves outside the chamber 1 towards the toroid 6, but inside the chamber 1 away from the toroid .6. This may be achieved by fitting a split flexible material top to the chamber 1 and inclining the hook 2 so that the slit closes up after it to hold the wire 5 captive. p

The machine shown in Figs. 3 and 4 has a circular .wire chamber 7' on a base 8. The hook 9 is carried by an arm 10 from a gearbox 1 1 driven by a motor 12. A suitable arrangement, not shown, is included forpositioning the hook 9 above the wire chamber 7"Wh6Il except that in this example, the book 2 is caused to, en-

gage the wire in a downward movement instead of an upward movement. Fig. 5 shows a circuit diagram of,the driving and sequence control equipment. Figs. 4A and Sshould be referred to, in conjunction with each other,

.as the operation of the machine isdescribed. Figs. '6 A and 6B show various stages of the booking operation.

' The toroid 6 (Fig. 4A) is held in position by clamping device 16, and the wire transporting device, i.e. pulley 3, mounted on pillar 17, is rotated around the toroid by a gear-cut ring 18 driver by motorMl, via

19. A cut-away portion 23 on the inner periphery of the ring is utilized to cause roller 24 to move in the direction of arrow C and operate changeover switch C1 (Fig. 5), controlling motors M1 and M2, when the wire transporting device has reached a position where the wire loop can be readily hooked-E by hook 2; this operation will be more fully described later. The camlike surface 32, on inner periphery of ring 18, causes roller 33 to move in the direction of arrow D once per revolution of ring 18 to operate counter CT (Fig. The hook 2, is mounted on the plunger 31 of solenoid S1. When S1 is energized, the hook is moved forward in the direction of arrow A against the pressure of return spring 26 until prevented from moving further 'by adjusting collar 27. At the end of this stroke hook 2 is positioned above the loop, between the toroid and the wire transporting device pulley, formed by the wire. Movement of the hook in the downward direction to such a position where it can engage the wire during its return stroke is accomplished by solenoid S2 of Fig. 4A, which, when energized causes its plunger 28, on which solenoid S1 is mounted, to move downward in the direction of arrow B against the pressure of return spring 29, until prevented from travelling further by adjusting collar 30. The sequence in which solenoids S1 and S2 are energized and de-energized during the wire application cycle is controlled by a series of cams, driven by motor M2. These cams cause pairs of contacts to close or open to disconnect or connect the DC. supply to the solenoids at various set intervals of time between rotations of the wire transporting device carrying pulley 3. These occurrences will now be described with respect to the sequence in which turns of wire are applied to toroid 6, and with reference to Figs. 4A, 5, 6A and 6B. Initially the cams and pairs of contact appendant to motors M1 and M2 rest in the positions shown in Fig. 5, the power supply to motors M1 and M2 is isolated by switch SW1. Gear-cut ring 18 is rotated to the position shown in Fig. 5 by handwheel 25, which is fitted to the output shaft of motor M1. This is the normal position in which the wire is unhooked from the wire transporting device carrying pulley 3. At this position the operating roller 24 for changeover switch C1 moves in the direction of arrow C and further disconnects M1 from the mains supply and connects M2. Since SW1 is still open, M2 remains inoperative. A piece of wire of the requisite length, has one of its ends twisted around the anchoring pillar 7 (Fig. 4A), and the other end is taken through the toroid toward the wire chamber 1, and then taken through the longitudinal split of wire chamber 1, so that it is now housed inside and gripped by friction pads 4. The wire has now assumed a position as shown in Fig. 4A, and the machine is now set for the automatic application of turns of wire to the toroid.

Initially changeover switch C1 and pairs of contacts C2 to C5 and earns MCZ to MCS which operate them, rest in the positions shown in Fig. 5. Push button start switch SBl is operated followed by isolating switch SW1. Switch SBl has a pair of normally open and a pair of normally closed contacts shown spaced apart on Fig. 5 for convenience. The normally closed pair are wired across the mains supply to motor M2, whilst the normally open pair are wired across the mains supply to motor M1. The operation of this button followed. by SW1 causes motor M1 to start and M2 to remain stationary. In consequence gear-cut ring 18 starts to rotate around the toroid, and as soon as it has rotated through 90, switch SBl is released. By this time changeover switch C1, operated by ring 18, connects the mains input to motor M1 which continues to rotate, thus driving the gear-cut ring 18 and pulley 3. The pulley engages the length of wire after approximately 200 of rotation and wraps the wire around the toroid section, at the same time withdrawing some of the free end of the wire from the wire chamber 1. As will be readily appreciated, the pulley 3 should be located in approximately the same plane as the end of the chamber 1 so that during its rotation about the toroid it will engage the section of wire between the toroid and the chamber 1. The end of the wire 5 is, however, secured to the pillar 7 at a point in a plane a short distance above the plane in which the pulley 3 rotates so that the pulley will pass beneath the section of wire 5 between the pillar 7 and the toroid. After the ring has rotated through a complete revolution, changeover switch C1 is operated, causing motor M1, ring 18, and pulley 3 to stop, and motor M2 to start. After 5 of rotation of M2, contacts C5 are operated to their closed position by cam MCS. Thus a hold-on circuit for M2 is completed, the reason for which will become apparent later in the description. After 10 of rotation of M2, contacts C3 are operated to their closed position by cam MC3 and the DC. supply circuit to solenoid S1 is completed. The plunger of solenoid S1 operates and carries the hook forward above the wire chamber 1, until it is in position over the loop of wire on pulley 3, as shown in Fig. 6A. After of rotation of M2, contacts C4 are closed by the operation of cam MC4 and the DC. supply circuit to solenoid S2 is completed. In consequence, plunger 28 moves downward, causing hook 2 to engage the loop of the wire, as is shown in Fig. 63. After of rotation of M2, contacts C3 are permitted to assume their open position by cam MC3 the solenoid S1 is deenergized and the hook is moved backward under the influence of return spring 26, Fig. 4A. Since contacts C4 are still closed and the hook is in the downward position, the wire loop is drawn into the chamber through the friction pads 4, Fig. 4A, and as the free end of the wire is drawn out, and in consequence clear of pulley 3, further movement backward of the hook draws the free end back into the tube 1. After approximately 270 of rotation of M2, contacts C2 to the mains supply and motor M1 are closed by the operation of cam MC2, and M1 starts to rotate to take gear-cut ring 18 and the pulley 3 through one revolution, during which pulley 3, again engages the wire in line between the toroid and the chamber to transport it to the hooking" position. Although, due to the rotation of M1 changeover switch C1 has operated to disconnect one circuit of the mains supply to M2, M2 will continue to complete its cycle since hold-on" contacts C5 operated by cam MCS, are still made, thus completing another circuit to M2, and they will continue to be made until M1 has made almost a completed revolution. Whilst M2 has been taking the gear-cut ring 18 and the wire transporting pulley 3 to the hooking position, contacts C4 opened and de-energized solenoid S2, and thus the hook has returned to its non-operated position. When M2 has completed a revolution hold-on contacts C5 are opened by the operation of cam MCS but by this time changeover switch C1 has been operated by ring 18 when the wire transporting device reached the hooking position. Thus the circuit to M2 is still closed via the switch C1 and the wire application cycle starts again. The continuous wire application process can be terminated after the requisite number of turns have been counted on counter CT, by opening switch SW1 as the wire transporting device approaches the hooking" position. Setting of the wire transporting device to the hooking position if it stops short can be accomplished by use of the handwheel 25 as already described. It may be necessary during adjustment and setting, to operate solenoids S1 and S2 independently of motors M1 and M2 and in consequence push buttons FBI and PB2 are provided and which, when pressed, lay-passed contacts C3 and C4 to connect the DC. supply to either or both of the two solenoids S1 and S2.

Fig. 7 shows the general arrangement ofa machine for automatically performing the functions of applying successive turns of wire on to a toroid in accordance with the principles outlined in the second embodiment, engagement of the wire in this instance being accomplished by lowering the hook as opposed to dropping the pulley.

As in the previous embodiment, the toroid 15 is held in position by clamping device 16, and the wire transporting device consisting of pulley 14 on pillar 17 is rotated around the toroid by a gear-cut ring 18 supported on rollers 19 and driven by motor M1 via reduction gears 20, 21 and 22. A cut-away portion 23 on the inner periphery of ring 18 is utilised to cause roller 24 to move in the direction of arrow C and operate pairs of contacts C3 and C4, Fig. 8, when pulley 14 has been positioned by ring 18 to a position where the wire loop formed can readily be hooked off by hook 9. This operation will be more fully described later. As in the case of the first embodiment, the cam-like surface on the inner periphery of ring 18 causes roller 33 to move in the direction of arrow D once per revolution of ring 18 to operate counter CT (Fig. 8).

In the embodiment being described, the wire chamber '7' is circular in shape and mounted on supports 34, the

advantage of this circular form of chamber being that greater lengths of wire canbe accommodated. The hook 9 is mounted on arm which can be rotated in alternate clockwise and anti-clockwise directions since it is mounted on shaft 35 driven by motor M3 via reduction gears 26' and 27. Arm 10 is pivoted about spindle 32' of a fulcrum arrangement incorporated in the housing of solenoid S1 such that at the end of each clockwise rotation, i.e. when hook 9 is in the position shown by the dotted outline designated by the reference 9A, solenoid S1 is energized and causes the outer extremity of arm 10 to move downward against the pressure of return spring 29 until prevented from moving further by adjusting collar 30. The hook is then engaged in the wire loop as shown by the dotted outline 9A. During the anti-clockwise rotation of .arm'10 to the position where the hook isshown in dotted outline and designated by reference-9B,- solenoidsl remains energized and therefore the loop is drawn into chamber 7 through friction pads '(such'as 13, Fig. 3) in a similar manner to that described for the first embodiment. At the end of the anti-clockwise rotation of the arm, by which time the book has been drawn free of the wire, solenoid S1 is deenergized and the hook is withdrawn vertically upward from the split chamber 7' ready for the next clockwise rotation. The next rotation however, does not take place until ring 18 with pulley 14 on pillar 17 has completed one revolution and is in the hooking" position. The sequence in which S1 is energized and deenergized during the wire application cycle is controlled by the oscillations of cam M3C fixed to shaft 35 on which arm 10 is fitted. This cam causes contacts C7 (see also Fig. 8) to be opened and closed at the end of each anti clockwise and clockwise rotation, respectively, of shaft 35. 7

It is the purpose of cam M3A, also on shaft 35, to operate reversal switch RS2 at the end of each clockwise and anti-clockwise rotation to reverse the direction of the drive from motor M3 and in consequence reverse the direction of rotation of the shaft 35 on which arm 10 is mounted. Cam M3B operates contacts C6 (see also Fig. 8) at the end of each anti-clockwise rotation of shaft 35 to break the circuit to motor M3 which is then prevented from making a rotation in the clockwise direction until ring 18 carrying pillar 17 with pulley 14 has completed a further revolution to form a loop of wire. Sequence control motor M2 has as its purpose the overall control and timing of successive wire application cycles. Its operation with respect to motors M1 and M3 will now be described as such control is exercised during the automatic wire application cycles.

Initially the cams and pairs of contacts appendant to motors M1, M2 and M3 rest in the positions shown in Fig. 8 (this figure should be referred to in combination with Fig. 7 during this description) and the power supply to all motors is isolated by switch SW1. The gearcut ring 18 is rotated to the hooking" position by handwheel 25, coupled to the drive shaft of M1. At this position the operating roller 24 for pairs of contacts C3 and C4 are operated to open C3 and close C4. A length of wire to be applied to the toroid is then twisted around anchoring pillar 37, taken once around the toroid section in an anti-clockwise direction and then taken through the split in the top of chamber 7' along its periphery until all of it is housed inside. The wire is held taut where it enters the chamber by friction pads 13 (see Fig. 3). The wire has now assumed a position as previously shown for the first embodiment in Fig. 4, and the machine is now set for the automatic application of turns of wire to the toroid. The hook 9 on arm 10 should be positioned to its extreme anti-clockwise position either by a handwheel 33 on the drive shaft from motor M3, or by the reversal switch RS1 (the operation and function of which will be described later). This position is shown by the 'dotted outline designated 9B,'and movement of arm 10 it has opened contacts C7 to de-energise it; S1 stays deenergised on each successive clockwise rotation of shaft 35, and at the end of each of these rotations contacts C7 are closed to energise it for each anti-clockwise rotation.

Cam M2A on the drive shaft of motor M2 is utilised to start motor M1 through contacts C1 after switch SW1 is closed and cam M2B is utilised to start motor M3 at some time later-through contacts C2, these operations occurring during the wire application cycle. Contacts C4 in series with contacts-C2 ensure that motor M3 cannot start and cause shaft 35 to rotate arm 10 and book 9 until ring 18 with pulley 14 has rotated once and formed a loop of wire. When at the commencement of the automatic wire application operation switch SW1 is closed, motor M2 starts, cam M2A rotates and causes contacts C1 to be closed and complete the supply circuit to motor Ml which starts to rotate as does gear-cut ring 18. In consequence contacts C3 are closed to complete a hold-on" circuit for M1. M1 will rotate to cause ring 18 to make one complete revolution and in doing so pulley 14 will engage the wire between the toroid and the chamber, form a loop, and stop at the hooking position when contacts C3 are opened. During the period of rotation of ring 18, cam M2A on the shaft of motor M2 has rotated a requisite number of degrees to cause contacts C1 to be opened. Almost immediately after ring 18 has stopped, cam M2B causes contacts C2 to close and complete a circuit for motor M3 which commencesto rotate in -a clockwise direction as do cams M3B and M30. Almost immediately cam M3B closes contacts C6 to complete a hold-on circuit for motor M3.- :Toward the end of the, clockwise rotation of shaft 35, arm 10 and hook 9, cam M3A on shaft 35 causes reversal switch RS2 to operate and reverse the direction of rotation, and at the same time cam M3C causes contacts C7 to close and energized solenoid S1. Hook 9 on arm 10 is therefore directed downward to engage the wire loop as shown in Fig. 6B of the first embodiment. Arm 10 is now rotating in an anti-clockwise direction and the free end of wire is drawn out of the chamber around the pulley 14 and back into the chamber through the friction pads, wrapping itself around the rest of the toroid in the process. Solenoid S1 stays energisedduring this anti-clockwise rotation. Toward the end of the rotation cam MZB cause contacts C7 to open, but hold-on contacts C6 remain closed and thus the rotation continues until cam M3A causes reversal switch SW2 to operate ready to drive shaft 35 in a clockwise direction again. This reversal procedure is immediately followed by the opening of contacts C6 by cam M3B to stop motor M3 and thus rotation of shaft 35. At the same time contacts C7 are opened by cam MSC and S1 is de-energised causing hook 9 on arm 10 to move vertically upward clear of the chamber since by this time, the hook has cleared itself of the free end of Wire. At this instant motor M2 is still driving cams M2A and M2B, and pairs of contacts C1 and C2 are still open and in the position shown in Fig. 8. If switch SW1 is still closed at this time, the closing of contacts C1 will cause motor M1 to start and the wire application cycle to start all over again.

To stop the cycle, switch SW1 is operated toward the end of an anti-clockwise rotation of shaft 35. If the shaft stops short of the full anti-clockwise rotation it can be positioned correctly to the start position by rotating handwheel 33' on the output shaft of motor M3 until switch RS2 is heard to operate.

For the purposes of setting and adjustment the shaft of motor M3 can be rotated in a clockwise or anti-clockwise direction by the use of reversal switch RS1 which by-passes SW1 to the main power supply and also RS2. However as a safety precaution, the pre-set speed control SC prevents motor M2 driving at the normal speed during such times that RS1 is being used. Limit switches LS1 and LS2 prevent motor M3 from over running in either direction when RS2 is rendered ineffective through the employment of RS1. Operation of solenoid S1 for setting and adjustment may be accomplished by the use of press button PBl which by-passes contacts C7.

Whilst means for holding the toroid in a stationary and rigid position during the application of turns in pile form has been shown in Figs. 4 and 7, it is often necessary to apply turns evenly, around the whole or part of the toroid section, thus the toroid must be rotated or reciprocated about its centre by some means during the successive wire application cycles. If reference is made to Fig. 9 a perspective of an arrangement for achieving rotation of a toroid 51 is shown. The toroid is supported at three points by

rollers

38, 39 and 40, roller 40 being located on a moving arm 41 pivoted about 42 and

rollers

38 and 39 being mounted on a support 50. The arm is spring loaded to cause roller 40 to move in the direction of arrow A thus preventing the toroid from falling out of support. Fig. 10 shows the toroid in section and the general form of roller 40;

rollers

38 and 39 are of similar form. Whilst roller 40 is free to rotate, both

rollers

38 and 39 as shown in Fig. 11, are locked on shafts to which spur gears 44 and 45 are fitted. These gears are in turn driven by spur gear 46 wheel and worm 47 and worm 48 driven from some driving source via shaft 49 and at a speed determined by the lay or spacing of successive turns required. Such anarrangement, when used with the embodiments described can be made to rotate the toroid continuously at either desired rate in any direction during the wire application cycle, to rotate it to a new angular position between the end of movement of the hook back into the wire chamber and the rotation of the pulley of the wire transporting device, or to reciprocate the toroid during winding. In the first embodiment, these operations could be timed by an additional cam on the shaft of motor M2, which would cause pairs of contacts to open and close to either drive the toroid in one direction or another or to stop the motor driving shaft 49 at requisite times during the wire application cycle. Such a cam on the shaft of motor M2 of the second embodiment could perform the same functions.

While the principles of the invention have been described above in connection with specific embodiments, and particular modifications thereof, it is to be clearly understood that this description is made only by way of example and not as a limitation on the scope of the invention.

What we claim is:

1. A toroidal coil winding machine comprising a holder for holding a toroid core in position for winding successive turns of wire thereon, a wire-positioning device on one side of 21 positioned core for positioning a length of wire, an anchoring device offset from the core for anchoring one end of the length of wire which has been threaded through the core from the wire-positioning device, a wire-transporting device and means for rotating it in one direction about the core in a path passing between the core and the wire-positioning device to engage the wire extending therebetween and to transport a loop of said wire around to the other side of the said core, and means reciprocable from the said wire-positioning device for passing through the core to engage the said loop and to return to the said wire positioning device withdrawing the loop and the free end of the wire through the core into the positioning device for further engagement by the said wiretransporting device.

2. Machine as claimed in claim 1 in which said lastnamed means comprises a hook device normally positioned on the same side of the toroid holder as said wire-positioning device and arranged to be passed through the toroid to engage the said loop of wire and to withdraw with the wire into said wire-positioning device to a point where the wire is released from said hook device.

3. Machine as claimed in claim 1 further comprising means for rotating the toroid during winding to control the location of the turns wound thereon.

4. Toroidal winding machine according to claim 1, in which said wire positioning device comprises a straight tubular member and said last means comprises a hook member, and means for imparting to said hook member reciprocating movement in a linear direction.

5. Toroidal winding machine according to claim 1, in which said wire positioning device comprises an arcuate tubular member and said last-mentioned means comprises a hook member, and means for imparting to said hook member reciprocating movement over an arcuate path.

References Cited in the file of this patent UNITED STATES PATENTS 2,812,143 Goodykoontz Nov. 5, 1957 FOREIGN PATENTS 202,870 Australia Aug. 2, 1956