US2971706A - Variable pitch coil winding machine - Google Patents

Description

Feb. 14, 1961 E. A. ELLIS ETAL VARIABLE FITCH coIL WINDING MACHINE 9 Sheets-Sheet 1 Filed May 28, 1958 Feb 14, 1951 E. A. ELLIS ETAL VARIABLE: FITCH con. WINDING MACHINE NLE 5 EL I EMM@ @I imm@ I I n pv 9 E 5@ Filed May 28, 1958 Feb. 14, 1961 E, A, ELUS ETAL 2,971,706

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COA/1190A United States Patent 2,971,706 Patented Feb. 14, 1961 VARIABLE PITCH COIL WINDlNG MACHINE Edward A. Ellis, Reading, Edward T. Stocker, Groveland, Robert A. Waddell, Winthrop, and Richard R. Whipple, Haverhill, Mass., assignors to Western Electric Company, Incorporated, New York, NX., a corporation of New York Filed May 2S, 1958, Ser. No. 738,419

7 Claims. (Cl. 242-9) This invention relates to winding machines and particularly to machines for winding spool type coils and precision spaced grids for electron tubes.

With the trend to higher frequencies in communication systems, there has been a corresponding increase in the degree of precision required in the pitch of single layer inductors. The windinfr machines commonly used heretofore were of the gear transmission type and the distribution (pitch of helical lay of wire on a core tube) could be set only at one of a limited number of discrete values. This was undesirable because many high frequency inductors fell between these values and made it dicult to wind the coils within the proper limits due to the very low tolerances permitted. Also, there were many possibilities of mechanical inconsistency in distribution formed by the Old machines due to their chain drives, cams and multiple gear trains. Even with a constant setting, deviations in inductance were undesirably large with certain inductors.

T'ne object of this invention is a machine capable of winding in a precise manner a single layer coil of any constant pitch to produce a coil having any prescribed value of inductance.

In a preferred embodiment, a guide for distributing the wire on a winding core is driven by a lead screw through a distributor lever which is moved about a fixed pivot by a motor driven lead screw. The lever, near one of its ends, is slidably and pivotally supported on a carriage driven in one direction by the lead screw during the winding operation and restored to start position by a quick return mechanism.

An adjustable tailstocl: is provided for receiving lead screws of different lengths to form windings of dierent pitch ranges and to control circuits for automatically tixing the safe maximum rate of carriage Vtraverse for each pitch range.

An adjustable stop on the lead screw iiXes the position of the carriage with respect to the start of the thread and the chucks for the winding core are rotatably adjustable to align the start of the winding relative to the start of the thread.

An important feature of the invention is the determination of the winding pitch by selecting the lead screw having the proper range and adjusting the lengths of the distributor lever arms relative to the xed pivot point.

Another feature of the invention is a mechanism for varying the pitch near the termination of the winding resulting in the winding wire being positioned at the terminal or the winding core after each winding.V

Still another feature is a mechanism for automatically lifting the wire guide from the winding core to clear the projected terminal or" the core at the termination of the winding.

Thus, an automatic winding of a precision pitch single layer inductor results wherein the distribution can be set at any particular value in the whole range of the combined number of lead screws.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, in which:

Fig. l is a schematic view of the apparatus embodying the invention;

Fig. 2 is a sectional View of the split nut assembly and elevational View of relative components of Fig. 1;

Fig. 3 is a sectional View of the toggle mechanism;

Fig. 4 is a sectional View taken along the line 4-4 of Fig. 3 and the clutch assembly;

Fig. 5 is a side View of the wire lifting mechanism;

Fig. 6 is the end view of Fig. 5, and

Figs. 7, 8 and 9 are diagrams of the electrical circuit for the apparatus embodying the invention.

With respect to Fig. l, the invention is illustrated as being incorporated in a special pantograph system whichconsists of a distributor lever 1l), having a telescoping sleeve 11, and three pivot points at 12, 13 and 14. Anyl one of the three pivots may be permanently secured to the chassis, however, pivot 12 is preferred in this embodiment and the front pivot 13 is connected to a carriage assembly 15 mounted on a chain 16 to travel parallel with the lead screw 17. The pivot in a dove tail when adjusting the point of force to be applied to the lever 10. Extending from the bearing assembly '27 of pivot 13 is a shaft 18, shown in Fig. 2, which causes the pivot to slide freely on the lever 10vin order that the straight line motion of the carriage 1Sy can be converted to a radial sweep motion about the pivot 12. Directly to the rear of the chassis pivot point 12 is a third pivot 1L?. mounted to the distributor head assembly 19 in such a manner as to travel parallel with the lead screw (Fig. l). The function of the 'head assembly is similar to that of the front pivot 13 and carriage 15 except it converts the radial sweep motion about the pivot 12 back to straight line motion in the distribution drive shaft 67 which carries the winding mechanism.

The winding pitch is determined by using a lead screw having a suitable pitch and adjusting lthe relative lengths of the two arms of the distributor lever 10 relative to the chassis pivot point 12. The carriage assembly 15, driven by the lead screw and moving alonlT guide bars 59, in'- cludes a micrometer 6l) for setting an index bar 61, having notches 62, parallel to a ratio adjusting screw 63. rihe carriage 1S, when positioned to the extreme right, is parallel to the lever 16 which can be either shortened or `lengthened by moving the pivot 13 along the carriage dove tail. A coarse adjustment may be obtained inthe upper arm of the lever by pulling the index pin 25 out from an opening tit) in the slide 65. The pivot block S6, having rollers 57, is moved along the lever causing the. pivotal member to move along the slide 65 to the desired location on the slide. The pin is then inserted and locked in the slide. In this manner the length of the upper arm 4may be adjusted relative to the chassis pivot point v@12.

A further tine setting is obtained by Yunlocking the front pivot 13 from the carriage 15, by loosening the set screw 64, as shown in Fig. l. The index bar 61 is rotated to disengage an index pin (not shown)y from the notch 62. The index bar 61 is moved to the desired position and rotated back to re-engage the index pin in the specified notch. The micrometer 60 is set to a desired reading and the ratio adjusting screw 63 is turned to move the pivot 13 until the index bar contacts the micrometer. The pivot is then relocked to the carriage. Thus, for a given traverse of the carriage to the left, the movement of the wire guide 71 to the right can be increased or decreased accordingly, thus changing thewinding pitch to any desired value.

One of a plurality of interchangeable lead screws hav- 13 is fixed but adjustable;

ing various lengths and different pitches of the helical threads 21, is inserted between the rear of a spindle 22 and the front of the tailstock assembly 23. The head 24 of the lead screw 17 is preferably cone shaped having an arcuate slot extending fromV the apex partly therethrough, for engagement with the drive key 26 on the spindle 22. Directly behind the head 24 is a conventionally threaded area 28 having a stop gage 29 held by a lock nut 30 to act as a carriage stop when the carnage 15 is returned to the starting position at the termination of the winding.

The end 31 of the lead screw is locked into the tailstock assembly 23 by horizontally sliding the assembly until the tailstock center head 32 engages the lead screw and the hand wheel 33 is rotated to apply slight pressure on the lead screw. When this is done a cam 34 on the tailstock engages one of a plurality of iixed microswitches 35 having contacts LS1, L82, LS3 and LS4 respectively, each of which, when operated, operates the corresponding relay S1, S2, S3, or S4 (Fig. 7) which automatically connects into the circuit of the motor 84 driving the machine, a speed controlling potentiometer R1, R2, R3 or R4 (Fig. 9) which is preset to x the speed of the motor at a desired value. Hence, by making the screws of each pitch of such length that it positions the cam 34 opposite a particular switch 35, the machine can be automatically set to run at the maximum safe winding speed for each lead screw pitch. The direction of the rotation of the lead screw is determined by a rotation selector switch 36 which has contacts LS12 controlling forward and reverse motor relays FW and RW so that the same direction of carriage travel can be obtained with either left hand or right hand lead screws. For example, all right hand screws, as seen in Fig. l, may have an end ring 38 on the lead screw tail 31 for engaging plunger 37 of switch 36 to selectively operate the FW and RW relays.

Each lead screw has a split nut assembly 40 which connects the lead screw to the carriage by thumb nuts 42 and a solenoid SNS, the solenoid activating the split nut to open and close about the lead screw, as seen in Fig. 2. The split nut assembly has a cover 44 over the housing 43 wherein laterally disposed clamping jaws 45 are adjacent to the lead screw. The split nut has a cam guide 46 threaded onto theV cam guard 47 and mounted within the guard is a return spring retainer 48 having a Vcam return spring 49 on the clamping cam 50. A spiral spring 51 having studs 52 holds the jaws in open position away from the'lead screw.` However, when the winding SNS is energized, an actuating pin 53 forces the clamping cam head 54 between the laterally disposed jaws causing the jaws to rotate on their pivots 55 and grip the lead screw 17. The jawsk maintain the grip on the lead screw during the winding operation and after the wndinghas terminated, the solenoid is deenergized and the jaws open permitting the carriage to be returned quickly to the starting position against the stop gage 29.

Extending from the slide 65 in the distributor head assembly 19 is a distributor drive shaft 67 which extends to a bearing assembly 68. Adjustably mounted at 69 on the shaft 67 is a bracket assembly 70 consisting of a wire guide 71 having a guide arm 72 and tail 73 pivotally mounted at 74. During the winding of a coil, the carnage 15 is moved to the left by the lead screw 17 and the bracket assembly 70 moves to the right along its guide bar 80. At the last turn of the winding, the pitch is increased by an amount sufiicient to bring the end of the last turn exactly to the terminal 99. This is obtained when the guide tail 73 engages a micrometer head 75 causing the arm 72 to pivot at 74 against the tension 0f the spring 81 and increase the pitch ahead of its normal distribution rate resulting in Vthe winding wire being positioned at the core terminal 99. 'Ihe increase of the pitch is governed by the desired setting of the micrometer 76 on the Vernier T head 77. The micrometer may be moved either horizontally and/ Or vertically along the T head 77 to engage the tail 73 at diierent positions or if desired, the supporting member '78 holding the whole assembly may be moved to diiferent positions located at 79. Thus, pitch acceleration can be varied as required for diierent size coils by a particular adjustment of this assembly. When the carriage returns to the starting position, the bracket assembly 70 moves to the left causing the tail 73 to disengage from the micrometer head. 75 and a spring 81, attached to a member 82 on the pivot 74, returns the guide 71 to its normal position.

When the index solenoid is energized as explained below, it forces a plunger 91 against the spindle hand wheel 92 which is rotated until the plunger seats into an aperture provided on the hand wheel. When this occurs the threads of the lead screw are in perfect alignment with the split nut resulting in the split nut moving from the same point on the thread at the beginning of each winding. Also, the chucks 93 holding the winding core 94, are oriented with respect to the beginning of the winding so that the stop counter 95 and slowdown counter 96 may be precisely set in relation to the starting position for each winding period.

At approximately the start of the pitch acceleration of the wire guide 71, which runs in direct contact with the winding core 94 so as to insure a precise distribution of turns, means are provided for lifting the guide 71 to clear the projected terminal 99 on the core in such a manner as to lay the wire 97 of the winding in direct contact with that terminal at the termination of the winding. As seen in Figs. l and 4, as the spindle 22 rota-tes it drives a gear train 101 and a shaft 102 having a clutch housing 103 with a fixed rotating clutch ring 104 attached thereto. Within the housing 103 is a sliding clutch ring 105 connected to a sliding clutch shaft 106 which extends beyond the housing 103 and is joined to a cam shaft 107. The shaft 106 is surrounded by a shifter fork 108 and yoke 109 which is held together by fork pivot pins 110 having springs 111 attached to a toggle mechanism 112, as seen in Fig. 3. When the distributor moves along its distribution path, as seen in Fig. 6, trip iinger 113 located on the bracket assembly 70 contacts clutch trip 114 which pushes the cam shaft 107 axially until the toggle mechanism 112 moves beyond dead center and snaps the cam shaft forward causing the sliding clutch ring 105 to engage and mesh with the fixed rotating ring 104 to drive the cam shaft 107. As seen in Fig. 5, a guide lifter cam 115 having a follower 116 rotates with the cam shaft 107 causing the lifter shaft 117 and pad 118 to engage a screw stop 119 mounted on the wire guide arm 72. The Wire guide ann 72 pivots at 120 and is lifted from the Winding coreV '94 over the projecting terminal 99 in such a manner as to lay the wire adjacent to the terminalat the termination of the winding. At this time the machine is stopped by the preset stop counter 95. During the return motion of the carriage, the clutch rings 104, 105 are disengaged as trip linger 113 contacts the collar 121 on the cam shaft 107 pushing it back to reverse the toggle mechanism and the lifter cam 115 is returned to its normal position by the spring loaded sector gear 122.

In preparing for the actual operation of winding a coil, it is assumed that the carriage is in the starting position at the right end of the lead screw against the stop gage 29. Now, referring particularly to Figs. 7, 8 and 9, the operator closes the toggle switch D6 and pushes the index button D4 whereupon the index relay'IR is energized and locked up over a circuit extending through its D-F contacts. The closing of the H--K contacts of the relay IR supplies power to the index solenoid IS of Fig. 8 which forces a spring held plunger 91 against the hand wheel 92 and the A C contacts complete a circuit for the holding relay HR through the contacts H-J of the carriage returnV relay CRT (Fig. 7). The contacts A-C of the HR relay (Fig. 8) in closing energize the holding solenoid HS to hold the carriage in starting position against the stop member 29. In this position the contacts LS8 of the limit switch 83 (Fig. 7) are closed and the carriage stop relay CSR is energized. The contacts A-'C of this relay prepare a circuit Ifor the start button D3 through the D-F contacts of the operated holding'relay HR. Y

The hand wheel 92 is now rotated until the index plunger 91 engages an aperture in the hand wheel which is -then locked. The plunger operates switch LSS in the index solenoid 94)Y to extend the start circuit to the CRI relay. Thus, when the start button D3 is operated the machine will not start if the spindle is not properly indexed. However, if the spindle is properly indexed, upon pushing the start button D-3 the circuit to the control relay #1 CR1 is closed and it energizes over the circuit just discussed over the contacts of limit switches LS9, L86, and counter reset switch LS10. In operating, the CR1 relay locks up through the A-B contacts of the latch relay LR and its own D-F contacts. The A-C contacts of the CRI relay complete the operating circuit of the split nut relay SNR, The H-K contacts of the SNR relay (Fig. 8) when energized, supply current to the split nut solenoid SNS and the split nut closes connecting carriage 15 with the lead screw and operating the contacts LS-7 of the switch 39 which prepare a circuit Vfor the rotation selector switch LS12. When the CRI was operated, it opened its A-B contacts releasing the index relay 1R which opens its H K contacts disconnecting the power from the index solenoid IS and permitting the spring to Withdraw the plunger 91 from the hand wheel 92 thereby closing the limit switch LS11 in the solenoid 90. The closing of the switch LSH completes an operating circuit 1for the forward FW or reverse RW wind relay according to the position of the contacts LS12 of the manual rotation selector switch 36. The switch LS11 also energizes the magnetic clutch relay MCR which, in operating, closes its A-C contacts'to energize the magnetic motor clutch 85 (Fig. 8) and the motor 84 starts to drive the lead screw in the selected direction which drives the carriage 15 to the left and the distributorV bracket assembly 70 to theI right to wind the wire 97 on the winding core 94. Y

When the slowdown counter 9x? reaches its predetermined setting, contacts D2 close energizing the creep relay CRC which locks up through its own H-K contacts. As seen in Fig. 9, other contacts on the CRC relay disconnect from the motor 84 the potentiometer R1, R2, R3 or R4 lwhich has been controlling the speed of the motor and connect to the motor the fixed resistors 123 and 124 which reduce the speed of the motor to a creep until the setting of the stop counter 95 is reached and its contacts D1 close. The closing of the contacts D1 of the stop counter energizes the latch relay LR and it locks mechanically in operating position. In opening its A-B contacts, the latch relay LR releases. the CRI relay, the MCR relay, and the FW or RW relay. The closing of the A-C contacts of the LR relay lights the red lamp LP4 to warn the operator that the carriage has not been reset. The D-F contacts of the LR energize the magnetic brake relay MBR which, in turn, closes its contacts A-C energizing the magnetic brake 98 which stops the rotation of the motor 84. The motor clutch 85 has already been disengaged by the opening of the A-C contacts of the MCR relay. The MBR relay locks up through its own contacts F-D since the CRI relay has been released. Since the winding relay FW or RW is deenergized, the power has been removed from the motor and the machine is at rest whereupon the operator performs the necessary operations of securing the wire to the core terminal 99 and removing the coil from the machine.

In preparing to wind another coil, the counters 95, 96 are reset to the proper values whereby the counter reset limit switch LS is operated to energize the unlatching winding of the latch relay LR and the winding of the rcsetting relay RES. In operating, the RES relay opens its A-B contacts (Fig. 7) releasing the SNR relay which 6 opens its H-K contacts (Fig. 8) thereby releasing the SNS relay which allows the split nut to disengage from the lead screw. The D-E contacts of the RES relay in closing energizev the CRT'relay through the contacts of the CRI, SNR, and CSR relays, all of which are nowreleased, to complete the operating circuit for the CRT relay. The A-B contacts of the RES relay also release the CRC relay which restoresfthe normal eld connections to the motor 84 of Fig. 9. When the carriage return relay CRT is energized it locks up through its own A-C contacts. Its F-D contacts supply power to the magnetic return clutch 86 and to the coil of control relay CR2. The A-C contacts of the CR2 relay complete the circuit through the B-A contacts of the FW relay to the coil of the reverse contacter R, Fig. 7, which in turn closes the R contacts of the motor 84 causing the motor to run backwards. As seen in Fig. l, the engagement of the carriage clutch 86 causes the worm gear 87 to drive the Worm Wheel S8 and the sprocket 89 to return the carriage 15 to the starting position at the stop gage 29. At this time (Fig. 8) the carriage stop limit switch LSS closes energizing the carriage stop relay CSR and lighting the distributor reset lamp LPZ. In operating, the I-I-I contacts `of the CSR relay are opened, the CRT relay is released, releasing the magnetic return clutch 86 and dropping out the CR2 relay which deenergizes the reverse contactor R. The opening of the normally closed N-L contacts of the CSR relay releases the MBR relay and it in turn deencrgizes the magnetic brake. The distributor reset light shows that the machine is now ready to begin a new cycle.

It is to be understood that the above described arrangements are simply illustrative of the application of the principlesV of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

l. In a coil winding machine, chucks for holding a winding core, a lead screw, end members for holding the lead screw, means for driving theV chucks land lead screw, means for changing the speed 'of` the driving means, a carriage driven by the lead screw, a wire guide for guiding Wire from a supply to the core, a distributor mechanism actuated by the carriage for moving the guide to distribute the wire between starting and finishing positions on the core, means for adjusting the ratio of the movement of the guide to the movement of the carriage, means for disengaging the carriage from the lead screw and returning it to its starting position` and contacting means adjacent one end member of the lead screw for activating the speed changing means to cause the driving means to run at a predetermined speed according to the length of the lead screw held by said end member.

2. In a coil winding machine, chucks for holding a winding core, a lead screw, end members for holding the lead screw, means for driving the chucks and lead screw, a carriage driven by the lead screw, a wire guide for guiding wire from a supply to the core, a distributor mechanism actuated by the carriage for moving the guide to distribute the wire between starting and finishing positions on the core, means for adjusting the ratio of the movement of the guide to the movement of the carriage, means for disengaging the carriage :from the lead screw and returning it to its starting position, switches in spaced relation to one of the end members, means controlled by each switch for causing the motor to run at a particular speed, and a cam attached to said one end member for selectively operating the switches according to the position of said one end member when engaged with the lead screw.

3. In a coil winding machine, chucks for holding a winding core, a lead screw, end members for holding the lead screw, means for driving the chucks and lead screw, a carriage driven by the lead screw, a wire guide for guidingwire from a supply to the core, a distributor mechanism actuated by the carriage for moving the guide to distribute on the core a predetermined number of` turns of the wire at a predetermined pitch between starting and finishing positions on the core, means for reducing'the speed of the driving means when the winding approaches the completion of the predetermined number of turns, and means for moving the wire guide with respect to the carriage to vary the pitch of the remaining turns of the winding to complete the last turn of the winding at the finishing position.

4. In a coil winding machine, chucks for holding a winding core, a lead screw, end members for holding the lead screw, means for driving the chucks and lead screw, a carriage driven `by the lead screw, a wire guide for guiding wire from a supply to the core, a distributor mechanism actuated by the carriage for moving the guide to distribute on the core a predetermined number of Vturns of the wire at a predetermined pitch between starting and iinishing terminals on the core, means `for reducing the speed of the driving means when the winding approaches the completion of the predetermined number of turns, and means for lifting the guide to place the wire at the finishing terminal.

5. In a machine for automatically winding coils accurately toa prescribed value of inductance, chucks for holding a winding core, a lead screw, end members for holding the lead screw, means for driving the chucks and lead screw, a carriage driven by the lead screw, a wire guide for guiding wire from a supply to the core, a distributor mechanism actuated by the carriage for moving the guide to distribute the wire between starting and finishing positions on the core, means for orienting theV starting position of a core in the chucks with respect to the start of the thread of the lead screw, a starting circuit f or the driving means, means for counting the turns applied to the core, means energized by the counting means' for stopping the chucks and means for disabling the starting circuit until the core has been oriented with the lead screw.

6. In a coil winding machine, chucks for holding a winding core, a lead screw, end members for holding the lead screw, means for driving the chucks and lead screw, mechanism for distributing Wire on the core, a carriage for drivingthe mechanism, anormally open split Vnut for connecting the carriage to theplead screw, a solenoid for closing the nut on the screw, a switch closed when the carriage is connected to Vthe lead screw, another switch closed by the carriage when it is in a predetermined position on the screw, and means` effective only when both the switches are closed for energizing the driving means.

7. In a coil winding machine, means supporting a winding core, a lead screw, a motor for driving the screw and the core, a carriage adapted to be driven bythe lead screw from a start position to a finish position to distribute wire on the core, a rst clutch for connecting the driving motor to the lead screw, a brake for stopping the lead Screw, mechanism for returning the carriage .to the start position, a second clutch for connecting the motor to the return ,-mechanism, means for counting la predetermined number of turns on the core, an electrical circuit having a rst pair of contacts for energizing the clutch and a second pair of contacts for energizing the brake, said counting means being connected in the circuit, means responsive to the counting means for operating the iirst and second pairs of contacts to release the rst clutch and operate the brake when a predetermined number of turns has been applied to the core, relays in the circuit for reversing the motor and operating the second clutch to return the carriage to start position after the brake has been operated to stop the lead screw, the first land second pairs of contacts being closed when the counting means is reset for energizing the relays, and further contacts in the circuit operated by the carriage when returned to its starting position for conditioning the machine to wind another coil.

lReferences Cited in the le of this patent UNITED STATES PATENTS 665,015 Kennedy Jan. l, 1901 2,360,960 Martindell Oct. 24, 1944 2,533,382 Lorenz et al. Dec. l2, 1950 2,703,207 Moore Mar. 1, 1955

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