US3044529A - Overwind device - Google Patents

Description

y 1962 A. o. WOLLENTIN 3,044,529

OVERWIND DEVICE Filed Jan. 14, 1959 2 Sheets-Sheet i FIG. 5. FIG. 7.

58 so 40 5e 60 40 IN V EN TOR.

y 1962 A. o. WOLLENTIN 3,044,529

OVERWIND DEVICE Filed Jan. 14, 1959 2 Sheets-Sheet 2 Fl. FIG.2. G

BYW

United States Patent Ofilice 3,644,529 Patented July 17, 1962 3,044,529 OVERWIND DEVICE Alvin O. Woilentin, Bloomfield, N.J., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Jan. 14, 1959, Ser. No. 786,824 5 Claims. (Cl. 153-67) The present invention relates to coil-winding machines and, more particularly, to an improved overwind device for such machines.

In the manufacture of coiled filaments for incandescent lamps and the like it is necessary (in order to accurately mount the filament on thelamp stem) that the straight uncoiled end-leg portions extend from the coil or body portion of the filament with the same predetermined angularity and in the same plane.

I Heretofore it has been known to wind coiled filaments on an automatic coil-Winding machine of the type shown in US. Patent No. 2,179,296, issued November 7, 1939, to F. B. Iden. In a coil-winding machine of this type the end of uncoiled wire is fed from a reel through a pair of jaws and a coiling die, parallel to a retractable mandrel, and the end is clamped by a wire-gripping finger on the nose of the rotatable coiling head to form the first straight uncoiled end-leg portion parallel to the longitudinal axis of the body. The reel, coil-guide head and coiling die are mounted on a wire-feed-gripper slide movable longitudinally with respect to the axis of the mandrel, which is retractable into and rotatable with the coiling head. The wire-gripping finger holding the end of the uncoiled wire adjacent and across the mandrel rotates with the mandrel and the coiling head about the mandrel axis to coil the wire around the mandrel and thereby form the coil. The coiling head is rotated a predetermined number of revolutions to produce a definite number of turns in the coil body. Simultaneously with such rotation the wire-feed-gripper slide is retracted longitudinally at a relatively slow rate in a direction away from the mandrel to provide a definite turns per inch in the finished coil.

At the completion of the coil-winding operation the mandrel is further retracted at a faster rate to form the second straight uncoiled leg portion on the filament, parallel to the longitudinal body of the coil. The mandrel is withdrawn from the coil and the second leg portion of the coil is cut a required distance from the mandrel whereupon the wound coil springs back a certain amount upon release from the coiling die. The first leg of the filament is then released by the wire-clamping finger thereby permitting the finished filament to fall from the coil-winding machine into a suitable container.

In order to compensate for the amount of spring-back in the coil (which varies from reel to reel of uncoiled Wire and depends upon the individual characteristics of such wire) it has been known to use a conventional overwind device of the type shown in US. Patent No. 2,439,893, issued April 20, 1948, to F. B. lden which device adds an additional fraction turn to the body of the wound coil. This overwind device is utilized with a coil-winding machine which winds a coil having the straight uncoiled endleg portions extending transverse from the coil body. Such prior-art overwind device has a cam and gear arrangement for rotating a carriage (which is slidable longitudinally of the mandrel axis and which carries the wiresupply reel on its spindle) through a predetermined angle about the mandrel axis and at a uniform rate with respect to the rotation of the mandrel and the coiling head to add or subtract a fraction of a turn from the coil, thus providing compensation for the spring-back of the coil on the mandrel when it is released therefrom, and

back lash between the separate drives (due to the high rotational-inertia of the carriage) often causes inaccuracies in the desired overwind and non-uniformity in the wound filaments. Further, considerable wear is encountered in the many moving parts of the conventional overwind device as disclosed in the above-mentioned patent, with re-' sultant maintenance problems and lost production time. Again, a machine of this type is subject to the further objection that the overwind device is not readily accessible for maintenance and hence requires complete dismantling of the device for the service of any of its parts. In addition, the cost of this complex prior-art device closely approximates a good proportion of the total cost of the entire coil-winding machine. 7

A further disadvantage of this conventional overwind mechanism resides in the fact that it is rotated to its starting position during the return of the wire-feed-gripper slide to its starting position and the presentation of the cut end of the uncoiled wire to the wire-gripping finger preparatory for the winding of the next coil. Such rotation of the cut end of the uncoiled wire during the return movement too often causes such end to strike the open wire-gripping finger and makes securement of such end therein impossible.

Another disadvantage of this prior art overwind de vice occurs with respect to the desired uniform angularity of the straight uncoiled leg portions of the coil with respect to the coil body. Even though such overwind device provides for spring-back in the coil body by the addition or subtraction of a fractional turn to the coil body no provision is made to prevent bowing of the second uncoiled leg portion when it is formed, since such second leg portion is under bending stress during its formation due to the formation of a sharp radius betweenthe end of the coil and the leg portion.

It is the general object of the present invention to avoid and overcome the foregoing and other difficulties of and objections to prior art practices by the provision of an improved overwind device having a low rotational inertia which eliminates back-lash in the moving parts and provides a consistent desired overwind with resultant uniformly wound filament coils.

A specific object of the present invention is the provision of an improved overwind device which is readily accessible for any required maintenance, is simple in construction, has relatively few moving parts, and is low in manufacturing cost.

A further object of the present invention is the provision of an improved overwind device which rotates to its starting position during the formation of the second straight uncoiled leg portion, thereby eliminating rotation of the cut end of the uncoiled wire during the presentment of such cut end to the wire-gripping finger for securement of the lattertherein preparatory for the forming of the next coil.

Yet another object of this invention is the provision of an improved overwind device which utilizes its rotation to the starting position (during the formation of the second straight uncoiled leg portion) to rotate such second uncoiled leg portion during its formation to prevent bowing in such second uncoiled leg portion and to provide' a straight second leg portion and the same desired angularity with respect to the coil body in such second leg portion as in the first leg portion.

The aforesaid objects of the present invention and other objects which will become apparent as the descriptracting a fraction of a turn to the coil to insure the disposition of theleg portions of the coil in the same plane and means for returning the coiling die to its starting position during the formation of the second straight uucoiled leg portion to provide a straight second leg portion. a t

For a better understanding of the present invention reference should-be had to the accompanying drawings, wherein like numerals of reference indicate similar parts throughout the several views and wherein:

FIG. 1 is a fragmentary side-elevational view of the essential portions of a coil-winding machine of the type shown in the above-mentioned US. Patent No. 2,179,-

296, which machine incorporates the improved overwind device of the present invention and shows such overwind device in the latched position at the end of its return movement. I

FIG. 2 is a perspective view of the improved overwind device shown in FIG. 1.

FIG. 3 is a fragmentary side-elevational view of the cam means and associated rack utilized. to drive the improved overwind device and showing the rack in the unlatched position preparatory for the starting of a winding cycle.

FIG. 4 is a fragmentary side-elevationalview of the coiling die and a portion of the wire-feed-gripper slide, the parts being shown in their positions at the start of the winding cycle and corresponding in time to the showing in FIG. 3.

FIG. 5 is a view similar to 'FIG. 3 and showing the rack at the end of the overwind operation.

' FIG. 6 is a view similar to FIG. .4 and showing the amount of the overwind provided in the finished coil.

FIG. 7 is a view similar to FIGS. 3 and 5 but showing the latched position of the rack at the end of its return movement. FIG. 8 is a view similar to FIGS. 4 and 6, taken alon the lines VIIIVIII of FIG. 1 in the direction of the arrows and illustrating the return movement of the coil: ing die preparatory for the presentment of the cut end of the uucoiled wire to the wire-clamping finger during movement of the wire-feed-gripper slide.

FIG. 9 is a vertical-sectional view taken along the; line IX-lXof FIG. 4 in the direction of the arrows showing the coiling die, associated die holder and pinion gear and a portion of the gear train used to drive the pinion gear.

FIG. 10 is a view similar to FIGS. 3, 5, 7 of an alternative embodiment of the overwind device of the' present invention where such device is utilized to sub tract a fraction of a turn from the body of the finished coil, showing the rack at the start of the winding opera 'Although the improved overwind device of the present;

invention may be used generally with coil-winding machines of other types, 'such device is more particularly adapted'for use in conjunction with a coil-winding machine of the type shown in the above-mentioned U.S. Patent No. 2,179,296 and hence it has been so illustrated and will be so described.

' With specific reference to the form of the present in vention illustrated in the drawings, and referring particularly to FIG. 1, a coil-winding machine of the type shown in the above-mentionedUS. Patent No. 2,179,296 is indicated generally by the reference numeral 10. Since the coil-winding machine 19, per se, forms no part of the present invention it is deemed sufllcient to only briefly describe its operation with respect to the improved overcoiling head 32, a predetermined number of turns in wind device of the present invention.

As shown in FIG. 1 a reel 12, which carries uucoiled wire 14, is mounted on a wire-feed-gripper slide 15 of the coil-winding machine -10; 'This slide is horizontally reciprocable by conventional means (not shovm) on a frame 17 of the coil-winding machine 10. To start the coil-winding operation, an end of the uucoiled wire 14 from the reel 12 is fed by hand successively through a stationary jaw '16 and movable jaw 13 (which has been opened by conventional operating-means 9) and through a longitudinal Wire hole 20 (FIGS. 4, 6, 8, 9 and 11) in a coiling die 22 (FIG. 2), with the end of the wire 14 projecting therefrom a predetermined amount. The jaws 16 and 18 are also mounted on the slide 15 and the coiling die 22 is secured in a die holder 23 (FIG. 9) which 7 holder is rotatable in the slide 15.

The coil-winding machine is then started. The end of the uucoiled Wire 14 is moved by the slide 15 parallel to a retractable mandrel 26 which has been automatically inserted (by conventional means not shown) in a longitudinal mandrel hole 28 in the coiling die 22 and such end is presented to an open wire-gripping finger 30 on the nose of a coiling head 32 of the coil winding machine 10, which finger has been opened by operation of the aforesaid conventional operating means 19. The wiregr-ipping finger 30 is thereafter automatically closed about the end of the uucoiled wire 14 and the movable jaw 18 is automatically opened by the same convention-a1 operating end-leg-potrtion 34 (FIG. 12) preparatory for the coilingoperation.

The Wire-gripping finger 36 (holding the end of the uncoiled wire 14 adjacent and across the mandrel 26) is rotated, along with the mandrel 26 which telescopically engages the hole 28 in the die 22 as a bearing and the counterclockwise direction about the longitudinal axis of the mandrel 26 (in the direction of the arrow shown in FIG. 1) by conventional means (not shown) to provide a predetermined number of turns in the coil body 35 (FIG. 12

Simultaneously with this counterclockwise rotation of the coiling head 32, the wirefeed gripper slide 15 is moved to the left, as viewed in FIG. 1, at a predetermined relatively slow rate by conventional means (not shown) to properly space the turns being'formed in the coil body 35. During this movement of the slide 15 the die holder 23 and the ceiling die 22 are rotated in counterclockwise direction, as viewed in FIG. 1, about the mandrel axis by the improved overwind device of the present invention thereby adding a fraction of a turn to the turns in the coil body 35. This added fraction of a turn compensates for the spring-back in the coil body 35 when the coil is completed and released from the coil-winding machine 10 as hereinafter related.

Overwind Device In order to cause this counterclockwise rotation of the coiling die 22 simultaneously with the rotation of the coiling head 32, a pinion gear 36 (FIGS. 2 and 9) 'afiixed to the die holder 23 and rotatable therewith is connected by a gear train 38 to a rack 40 which is vertically reciprocable in the wire-feed-gripper slide 15. This rack 40 has a roller 42 biased by a compression spring 44 into engagement successively with a stationary operating cam 46 and return cam 48. The operating cam 46 and the return cam. 48 are commonly pivoted at 50 on a plate 51 afiixed to the frame 17 of the coil-winding machine 10 and have their outer ends, as viewed in FIGS. 1 and 2, secured by suitable screws in annular adjustment slots 52 and 54 respectively, provided in the plate 51.

The improved overwind device of the present invention utilizes the abovementioned movement of the wire-feedgripper slide 15 to the left (during the rotation of the coiling head 32) to drive the overwind device. This movement of the slide 15 causes the spring-biased roller 42, carried by the slide 15, to ride upwardly on the stationary operating cant 46 (from the position shown in FIG. 3 to the position shown in FIG. 5) thereby causing the rack 40 to move upwardly, as viewed in FIGS. 1 and 3. This upward movement of the rack 46 is transmitted by the gear train 38 to the pinion 36 with resultant counterclockwise rotation of the latter, the die holder 23 and the coil die 22 (from their position shown in FIG. 4 to the position shown in FIG. 6), thereby causing the attendant addition of a fraction of a turn to the coil body 35. It will be understood thatsince the die holder 23 and coiling die 22 are light in weight, their rotational inertia is low thus eliminating back-lash in the moving parts and providing a consistent overwind in successive coils. It is obvious that the amount of overwind is controlled by the amount of vertical upward movement of the rack 40, which in turn is controlled by the angular displacement of the adjustable operating cam 46 with respect to the horizontal portion of the frame 17 (FIG. 2).

When the coiling head 32 and the coiling die 22 cease their counterclockwise rotation, as viewed in FIGS. 1 and. 2, and the coil body 35 is completed, the wire-feed gripper slide continues its movement to the left, as viewed in FIG. 1, at a relatively faster rate thanits previous rate of movement during the coiling operation to form the second straight uncoiled end-leg portion 56. It is obvious that the formation of the sharp radius between the end of the coil and the second straight uncoiled leg portion has stressed the leg portion 56 so that (contrary to the actual condition), if such leg portion 56 were free it would assume the bowed dotted-line position shown in FIG. 12. This continued movement of the slide 15 to the left causes the roller 42 to move from the position shown in FIG. 5 along the surface of the re-' turn cam 48 to the position shown in FIG. 7 with resultant lowering of the rack 40 to the position shown in FIGS. 1 and 2 and attendant clockwise retracting rotation of the coiling die 22 to its starting position shown in FIG. 8. Duringthis retracting rotation of the coiling die 22 the second straight uncoiled end-leg portion 56 is also rotated in like direction (at a faster rate than the natural uncoiling rate of the coil body 35 which is still on the mandrel 26) thus preventing bowing of the straight second leg portion 56 during its formation and providing a straight portion 56. This retractive rotation of the coiling die 22 also permits the coil body 35 to spring back while still on the mandrel 26, to align the second leg portion 56 along a line through the first end-leg portion 34.

When the roller 42 arrives at this position shown in FIGS. 1, 2 and 7, a latch 58 pivoted :at 60 on a bracket 62 afiixed to the wire-feed-gripper slide 15 slides into a notch 66 (FIGS. 1, 2, 3, 5, 7 and 11) provided in the left-hand face of the rack 49 thereby locking the rack 41 and the coiling die 22 in the position shown in FIGS. 1 and 2. The latch 58 is biased by a tension spring 64 (FIGS. 1 and 2) into engagement with the left-hand face, as viewed in FIG. 3, of the rack 40. Such spring 64 extends from a lug 65 projecting from the slide 15 to a rod 67 carried by the latch 58.

The mandrel 26 is then withdrawn from the mandrel hole 28 in the coiling die 22 and the second straight uncoiled end-leg portion 56 is then cut by conventional cutting means (indicated generally in FIG. 1 by the reference numeral 69) a predetermined distance from the coiling die 22, without any appreciable further spring back of the coil body 35. The first straight uncoiled leg portion 34 is released from the wire-clamping finger 30 by operation of the operating means 19 thereby permitting the finished coil to drop from the coil-winding machine 10 into a container (not shown). Operation of the operating means 19 also causes the movable jaw 18 to close 6 preparatory for the presentment of the cut end of the uncoiled wire 14 to the now open wire-clamping finger 30 during movement of the Wire-feed-gripper slide 15 to the right, as viewed in FIG. 1.

It ils obvious from a consideration of FIGS. 1, 3 and 4 that (during such movement of the wire-feed-gripper slide 15 to the right) the roller 42, locked in the position in FIG. 3, moves horizontally in the direction of the horizontal arrow shown in FIG. 3 from the dotted-line position, shown in such figure, to the solid-line position shown therein. As the roller 42 approaches such solid-line position shown in FIG. 3, the rod 67 on such latch58 engages the head of an adjustable stop: 68 mounted in a bracket 70 affixed to the plate 51, thereby rotating the latch 58 in a clockwise direction (FIG. 3) about its pivot 60 against the action of the tension spring 64, and moving such latch 58 out of the notch 66 preparatory for the next coil-winding operation.

' It will be recognized by those skilled in the art that the objects of the present invention have been achieved by providing an improved overwind device having a low rotational inertia thus eliminating back lash in the moving parts and providing a consistent desired overwind with resultant uniformly wound filament coils. Such improved overwind device is readily accessible for any required maintenance, is simple in construction, has relatively few moving parts and is low in cost. The device eliminates rotation of the cut end of the wire-gripping-finger for securement of the latter therein preparatory for the next coilwinding operation. In addition, the improved overwind device uses its retracting rotation to the starting position (during the formation of the second straight uncoiled leg portion) to rotate such second straight uncoiled endleg portion in a direction opposite to the coiling rotation thereby releasing any bending stresses therein and pro viding the same desired angularity in both leg portions.

As an alternative embodiment to the preferred embodiment shown in FIGS. 18, it is possible to subtract a fraction of a turn from the coil body 35. In such alternative embodiment shown in (FIGS. 10 and 11 the operating cam 46 and the return cam 48 may be positioned as shown in FIG. 10.

Then, during the above-described coil-winding operation the rack 40 is lowered, as viewed in FIG. 10, and the pinion 36, coiling die holder 23 and coiling die 22 are rotated in clockwise direction about the longitudinal mandrel axis, as viewed in FIG. 11 to subtract a'fraction of a turn from the total number of turns being formed in the coil body 35' by the coiling head 32.

While in accordance with the patent statutes one best known embodiment of the present invention has been i1- lnstrated and described in detail, it is to be particularly understood'that the invention is not limited thereto or thereby.

I claim:

1. An overwind device for a coil-winding machine having a coiling head rotatable to form a coil provided with a coil body, a first uncoiled end-leg portion and a second uncoiled end-log portion, said. overwind device comprising a coiling die, means connected to the coiling die for rotating it through a predetermined angle in one direction during the rotation of the coiling head to form the coil body thereby varying by a fraction of a turn the total number of turns in the coil body to insure the disposition of the uncoiled end-leg portions of the coil in the same plane, and means also connected to the coiling die for returning the coiling die to its starting position after the formation of the coil body, for rotating the second uncoiled end-leg portion and the coil body in the other direction during the formation of the second uncoiled end-leg portion thus providing a straight second uncoiled end-leg portion and for allowing the coil body to spring back thus aligning the first and second uncoiled end-leg portions in the same plane.

7 2. For a coil-winding machine having a wire-feed-gripper slide and a coiling head rotatable to form a coil provided with a coil body, a first uncoiled end-leg portion and a second uncoiled end-l eg portion, an overwind device comprising a coiling die, means connected to the coiling die for rotating the coiling diethrough a predetermined angle in one direction during the rotation of the coiling head to form the coil body and operable by movement of the wire-feed-gripper slide during the spacing of the turns in the coil body thereby varying by a fraction of a turn the total number of turns in the coil body to insure the disposition of the uncoiled end-leg portions of the coil in the same plane and means also connected to the coiling die for returning the coiling die to its starting position aiter the formation of the coil body and operable by movement of the wire-feed-gripper slide to rotate the second end-leg portion and the coil body in the other direction during the formation of the second uncoiled end-leg portion thus providing a straight, second uncoiled end-leg portion and to allow the coil body to spring back thus aligning the first and second uncoiled end-leg portions in the same plane.

3. For a coil-winding machine having a wire-feed-gripper slide and a coiling head rotatable to form a coil provided with a coil body, a first uncoiled end-leg portion and a second uncoiled end-leg portion, an overwind device comprising a. coiling die, rotating means connected to the coiling die, a first means operatively associated with the rotating means for causing rotation of the coiling die through a predetermined angle in one direction during the rotation of the coiling head to form the coil body and operable by movement of the :wire-feed-gripper slide during the spacing of the turns in the coil body thereby varying by a fraction of a turn the total number of'turns in the coil body to insure the disposition of the uncoiled endleg portions of the coil in the same plane and a second means also operatively associated with the rotating means for causing the return of the coiling die to its starting position after the formation of the coil body and operable by movement of the wire-feed-gripper slide to rotate the second uncoiled end-leg portion and the coil'body in the other direction during the formation of the second un-- coiled end-leg portion thus providing a straight second uncoiled end-leg portion and to allow the coil body to spring back thus aligning the first and second uncoiled end-leg portions in the same plane. I p

4. For a coil-winding machine having a wire-feedgripper slide and a coiling head rotatable to wind an elongated article into a coibprovided with a coil body, a first uncoiled end-leg portion and a second uncoiled end-leg portion, an overwind device comprising a coiling die, rotating means connected to the coiling die, a first means operatively associated with the rotating means for causing rotation of the coiling die through a predetermined angle in onedirection during the rotation of the coiling head to form the coil body and operable" by movement of the wire-feed-gripper slide during the spacing of the turns in the ooil body thereby varying by a fraction of a turn the total number of turns in the coil body to insure the disposition of the uncoiled endleg portions of the coil in the "same plane, a second means also operatively associated with the rotating means for causing the return of thecoiling' die to its starting position after the formation of the coil body and operable by movement of the Wire-feed-gripper slide to rotate the second uncoiled end-leg portion and the coil body'in the other direction during the formation of the second uncoiled end-leg portion thus providing a straight second uncoiled end-leg portion and to allow the coil body to spring back thus aligning the first and second uncoiled end-leg portions in the same plane and latching means on the wire-feed-gripper slide operable to lock the rotating means in its starting position to prevent rotation of the coiling die during presentment of an end of the elongated article by the Wire-feed-gripper slide to the coiling head for securement therein. 7

5. For a coil-winding machine having a Wire-feedgripper slide and a ceiling head rotatable to Wind an elongated article into a coil provided with a coil body, a first uncoiled end-leg portion and a second uncoiled end-leg portion, an overwind device comprising a coiling die, a rack reciprocable in the Wire-feed-gripper slide, gear means connected to the coiling die and to the rack for translating the reciprocating movement of the rack into rotational movement of the coiling die, a first cam ciated with the rack for causing the return of the coiling die to its starting position after the formation of the coil body and operable by movement of the wire-feed-gripper slide to rotate the second uncoiled end-leg portion and the coil body in the other direction during the formation of the second uncoiled end-leg portion, thus providing a straight second uncoiled end-leg portion and to allow the coil body to spring back thus aligning the first and second uncoiled end-leg portions in the sam plane, latching means on the wire-feed-gripper slide operable to lock the rack in its starting position to prevent rotation of the coiling die during presentment of an end of the elongated article by the wire-feed-gripper slide to the coiling head for secureme'nt therein, and stop means engageable by said latching means near the end of the presenting movement of the wire-feed-gripper slide to release such rack preparatory for the next coiling operation.

References Cited in the file of this patent UNITED STATES PATENTS 2,197,296 Iden Nov. 7, 1939 2,439,893 Iden Apr. 20, 1948 2,801,670 Wolf Aug. 6, 1957

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