US2372082A - Coiling machine for fine wire - Google Patents

Description

Patented Mar. 20, 1945 Fred B. Iden, Cleveland Heights, Ohio, assignor to General Electric Company, a corporation of New York Application May 5, 1941, Serial No. 391,882 1s claims. (o1. 14o-71.5).l

My invention relates to methods and apparatus for making laments and other types of resistance elements, such as electrodes, for incandescent and discharge lampsv as well as other similar devices. More particularly, my invention relates to a method and apparatus for coiling and otherwise shaping such filaments or resistance elements.

It is desired that such filaments have certain definite shapes in order to reduce the complexity and increase the performance and life of the electrical devices in which they are used. It has not heretofore been possible to manufacture certain preferred forms 'of filaments so cheaply and readily as to make them available for the less expensive electric lamps and similar devices. Anobject of my present invention is to provide a method and automaticapparatus for producing such elements cheaply on a commercial scale. Another object of my invention is to provide automatic apparatus for making resistancev elements, particularly filaments, having a coiled mid-portion and specifically shaped end or leg portions.

Another object of my invention is to provide apparatus for reshaping the end or leg portions of a filament. Other objects and advantages of my invention will appear from the following detailed description and from the drawing.

In the drawing, Fig. 1 is a side elevation of apparatus comprising my invention with a transfer mechanism in the process of carrying a filament from the coiling apparatus to the leg shapping mechanism; Fig. `2 is a horizontal section through the coiling apparatus; Fig. 3 is a side elevation of the leg shaping mechanism at 90 degrees to that of Fig. 1 and with onev portion broken therefrom along the line 3-3 of Fig. 1;

A (Fig. 1) and a second shaping operation at B.

The coiling operation, in-particular, is preferably performed by apparatus of the general type ydisclosed in the Illingworth Patent 1,771,927, although itis preferred that the specic apparatus correspond to that disclosed in Iden Patent 2,179,296 in that such apparatus performs the ticularly well adapted to operate withfthe present apparatus comprising my invention. The essential parts of said coiling apparatus, which are shown midway through their cycle of operation in Fig.2, start each cycle of operation with a movement of the coiling head I0 toward the mandrel I I and spindle I2. At this time, the mandrel Ilextends from the spindle I2 as shown and a short end of the filament wire I3 extends from the coiling head I0.' The shoe I4 on the end of the jaw I5 is also separated fromthe spindle I2 at this time so that the-forward movement of the coiling head I0 can continue until the end of'said filament wire I3 is located over the shoulder I6 of the spindle I2. During the movement, the mandrel II passes into the opening Il of the coiling head I0, which is parallel to that containing j from the spindle I2 at a very definite rate to cause the filament wire I3 to be wound around said mandrel II at a desired pitch. The coiling operation is complete when the correct number of turns have been made to form the coils of the center section I8 of a filament although the axial movement of the coiling head I0 continues until it takes the position shown in Fig. 2 before it stops.

At this time, the center coiled portion I8 of a filament is wound around the mandrel II and the opposite end or leg portionsv I9 and 2U extend in opposite directions therefrom. The end or leg portion 20 of the filament wire I3 between the coils I8 and the coiling head I0 differs from that at the opposite end of the coils I8 in that it is double. said leg or end portion 20 and in the next operation is cut in two by movement of the knives 2| and 22. This operation establishes the length o1' the filament 23 which is comprised of a coiled portion I8 and the end or leg portions I9 and 20' ofl equal length and allows an end section .20" of theflamcnt wire I 3 to extend beyond the coiling head I0 having alength correlaps the last step in that the stationary and movable jaws 24 and 25 of the transfer mechanism engage and prepare to grip the coiled portion I8 of the filament 23 before it is stripped from the mandrel The transfer mechanism corresponds closely to the mechanism disclosed in Illingworth Patent 1,733,882 assigned to the present assignee, and comprises a stationary jaw 24 attached to the arm 26 and a movable jaw 25 slidable in ways in the stationary jaw 24. rAt the moment the jaws 24 and 25 are carried to A, the roller 21 on the end of the lever 28 is in engagement with a high part of cam 29, and said lever 28, which is connected to :jaw 25 through link 38, holds said jaw 25 in the open position. The lever 28 is pivoted on the screw 3| held by arm 26 and, being under the influence of the spring 32, is turned about 'said screw 3| in accordance with the changes in shape of the cam 29. When the transfer mechanism is at its limit of movement, the arm 26 engages the stationary stop screw 33 in the adjacent portion 34 of the apparatus and the coiled portion I8 of the filament 23 is within a V notch in the stationary jaw 24. During this latter interval the jaw I on the spindle I2 is moved sideward so that the end or leg portion |9 of the filament 23 is released and the mandrel II is drawn into the spindle I2 so that the filament 23 is stripped therefrom. The stripping operation is possible only because the coils I8 have unwound a fraction of a turn due to the release of the end or leg portion 28' in the last period of operation. The

next operation follows immediately and consists in a movement of the `jaw 25 which causes it to engage and grip the filament 23. The jaw 25 is actuated by the rotative movement of the cam 29 which carries a low portion thereof below the roller 21 and occurs so rapidly after the mandrel |I is withdrawn that the filament 23 does not turn or twist from its known position. The following transferring operation is the result of a swinging movement of the arm 26 which carries it against the stop screw 35 and carries the filament 23'into the shaping mechanism at ment 23 is still tightly gripped by the transfer mechanism. The transfer mechanism now functions as a holder for the filament while the shaping operation is being carried on since the jaws 24 and 25 form the coiled portion I8 thereof into a rigid mass which does not allow the end or leg portions I9 and 2l' to move out of position during said operation.. This method of operation is preferred because the filament 23 tends to turn out of position since it has, prior to the time it was gripped by the transfer mechanism, uncoiled a portion of a turn and the end or leg prtions I9 and 2l' are no longer in the same plane.

When the transferring operation has beencompleted, the fingers 31 and 33 are moved down so as to clamp a short section of the les portions I9 and 2l' next to thecoiled portion I8 to the arms 3l'38 of the die block 36. The upper ends of said arms 3l'33' constitute separated supports for the filament ends. The fingers 31 and 38 are in reality separate slides within ways formed by the standard 39, the cover plate 48 and the slide blocks 4| and 42 (Fig.- 3) and are moved by the expansion of springs 43 (partly enclosed in a well, in each finger) when the pin 44 moves downward. The springs 43 butt against the cap plate 45 attached to standard 39, whereas the pin 44 is carried by a slide 46 in ways in the back of the standard 39 and extends through a slot in said standard 39 to adjacent slots in the back of the fingers 31 and 38. A U-shaped spring 41 in corresponding slots in the front face of the fingers 31 and 38 absorbs all lateral freedom of movement thereof so that they retain very definite positions at all times.

-The downward movement of the fingers 31 and 38 is matched by a corresponding movement of the movable dies 41 Aand 48 located adjacent thereto which movement ls continued until the dies have wiped the legs of said filament 23 down about the shaped sides cf the die block 36 as shown in Figs. 3 and 5.

The movable dies 41 and 48 are partially located within slots in the slide blocks 4| and 42 respectively and are carried downward by the corresponding movement of said slide blocks 4I and 42 and slide 46 which are interconnected by the pins 49; Slots 59 in the standard 39 give the pins 49 freedom vof movement whereas pins 5| attached to slide blocks 4| and 42 provide a positive-means of attaching the movable dies 41 and 48 and the slide blocks 4| and 42 together. Springs 52, which are located between the slide blocks 4| and 42 and an extending arm of the movable dies 41 and 48, keep said dies 41 and 48 against the fingers 31 and 38 and the legs I9 and 28'- of the filament 23 during most of the period of travel thereof but at the end of said travel the oblique end surfaces 53 of said dies 41 and 48 engage the ends of screws 54 and 55 and are forced` inward. This latter movement of the dies 41 and 48 forces the legs |9 and 20' of the filament 23 tightly against the die block 36 and completes the shaping operation.

The movable dies 41 and 48 and thengers 3 1 and 38 are now returned to their former position in order that the filament 2.3 can be removed from the .shaping mechanism. The return movements of the apparatus are in reverse order to the other movements thereof and are caused by an upward movement of the slide 46. The slide 48 is located in ways in the back of the standard 39 in which it'is held by the rplate 56 and is connected through yoke 51 and rod 58 to cam actuated means (not shown) connected to the coiling apparatus and transfer mechanism in order that it and the shaping mechanism will be operated at proper intervals.

The filament 23 is released from the transfer mechanism prior'to being taken from the shaping mechanism by a rotative movement of the.

paratus and of pushing the filament 23 from the shaping mechanism so that it falls into the chute 59 and is carried away from the apparatus.

At this time, the lament 23 (shown in Figs. 6 and '1) is comprised of acoiled mid-portion II, relatively short leg portions 66 lying very generally in a. plane parallel to the axis of the coiled portion I8, and longer leg portions II odset from opposite sidesof the 'coiled mid-portion Il and tions to ,spring back to the above position al-V though they were bent to the more oblique faces of the die block 36. The very ends 62 of the :til-

ament'legs I9 and 20' retain the greater portion of the bend which they have received, however, and are located at still another position.

What I claim as new and desire to secure by Letters Patent of the United States is: v

1. Apparatus for forming fllamentary resistance elements for electrical devices from a wire comprising a mandrel, means for coiling a portion of .the v.wire about the mandrel with a free end portion extending outward substantially parallel to the axis of the coil, means for stripping the coiled portion of the wire from said mandrel, means for gripping the wire at its coiled portion and transferring it to another location and end portion of said wire so that it extends laterally of the axis ofthe coil in a definite predey ring means being constructed and arranged to hold the filament in delinite predetermined relation to said means for bending the wire.

2. Apparatus for forming fllamentary resistance elements for electrical devices from a wire comprising a mandrel, means for coiling a portion of the wire about the mandrel with free end portions extending outward substantially parallel to the axis of the coil, means for stripping the coiled portion of the wire from said mandrel, means located adjacent the coiling apparatus for bending theend portions of the wire so that they extend laterally of the axis of the coil in a deiiportion of the wire, adie adapted'to engage sections of both uncoiled portions of said wire extending beyond the' coiled portion, fingers adapted to clamp said sections of the wire against the die, movable dies adapted to bend the free portions of said uncoiled end portions of. the wire termined direction, said gripping and transferportion of the wire, means located adjacent the coiling means for shaping the wire comprising a die adapted to engage sections of both uncoiled portions of said wire extending beyond the coiled portion, ngers adapted to clamp said sections of the wire against the die, movable dies adapted to bend the free portions of said uncoiled end portions of the wire intjo engagement withthe rstmentioned die to shape them and means for actuating the ngers and movable dies at proper intervals, and means gripping the coiledportion of the wire for transferring it to the last-mentioned means andholding it in position during the axis of the coil, a die member having sides sloping obliquely inward and downward from its .upper edges, means for holding the filament on said die with its said end. portions extending across the said edges of the die and laterally outi' tioned die member arranged to bend said iilament end portions down around the said edges of said first-mentioned die member and then against its said -sloping sides.

7. In a device of the 'character described for reshaping the ends of a lament coil having straight end portions extending'outward from opposite ends of the coil substantially parallel t0 the axis of the coil, a die member having sides sloping obliquely inward and downward from its upper edges, means for holding the filament on said die with its said end portions extending l across the said edges of the die and laterally into engagement with the first-mentioned die to shape them and means for actuating the nger v and movable dies at proper intervals. f

4. Apparatus for forming filamentary resistance elements for electrical devices from a wire comprising Imeans for coiling an intermediate portion of the wire, a die adapted to engage sections of both uncoiled portions of said wire ex tending beyond the coiled portion, fingers adapted to clamp said sections of the wire against the die, movable dies adapted to bend the free portions of said uncoiled end portions of the wire into engagement with the first-mentioned die to shape them, springs urging the iingers toward .the said first-mentioned die and the wire, means controllingthe movement of said lingers for carrying the movable dies against said wire to bend the end portions over the said rst-mentioned die, and separate means for forcing the movable dies toward said first-mentioned die to bend said outward beyond its said sides, means for clamping the filament end portions against said die member adjacent its said upper edges, and movable die members on opposite sides of said firstmentioned die member Iarranged to bend said filament end portions down around the said edges of said first-mentioned die member and then against its said sloping sides.

8..In a device of the character described for reshaping the ends of a filament coil having straight end portions extending outward from opposite ends of the coil substantially parallel to the axis of the coil, a die member having sides sloping obliquely inward and downward from its upper edges, means for holding the filament on said diewith its said end portions extending acrossthe said edges of the die and laterally outward beyond its saidsides, a pair of clampfilament down around thesaid edges of said rstmentioned die member',v and means for then causing said movable die members to move inwardly to press the said filament end portions against the sloping sides of said first-mentioned die member.

9. In a device of the character. described for reshaping the` ends of a filament coil having straight Yend portions extending outward from opposite ends of the coil substantially parallel to the axis of the coil, a 'die member having sides sloping obliquely inward and downward from its upper edges, means for holding the filament on said die with its said end portions extending across the said edges of the die and laterally outward beyond its said sides, a pair of independently movable clamping iingers mounted above said die member, movable die members mounted above said first-mentioned die member on opposite sides of said clamping fingers, and means forv moving said clamping fingers and movable diev members downward to iirst cause each of said lingers to clamp 'a part of an end portion of the lament with a definite pressure against said first-mentioned die adjacent one of its said upper edges and to then cause said movable dier members to bend the free end portions of said iilament down around the said edges of said first-mentioned die member, and means for then causing said movable die members to move inwardly to press the said filament end portions against the sloping sides of said first-mentioned die member.

10. In a device *of the character described for reshaping the ends of a iilament coil having straight end portions extending outward from l opposite ends of the coil substantially parallel to the axis of the coil, a die member having sides sloping obliquely inward and downward from its upper edges, means for holding the lament on said die with its said end portions extending across the said edges of the die and laterally outward beyond its said sides, a pair of slide members mounted above said die member and each carrying a downwardly extending clamping iinger movably mounted in said slide in alignment with one of the said edges of said die member, an angular movable die member pivotally mounted on each of said slide members at one side of the adjacent ringer, each of said movable die members extending downward from its pivot and then laterally toward the adjacent finger, means resiliently urging each of said die members about its pivot to hold its end against the adjacent nger, means for moving said slide members downward to firstl cause said fingers to clamp parts of the end portions of the lament against said iirst-men-tioned die member and, upon further movement, to cause said ends of the movable die members to bend the free end portions of the filament down 'around the said edges of said inst-mentioned die member, and means for then causing said movable die members to be pivoted under added pressure to press the said iilament l yond the supports, clamping said end portionsv against said supports, and then bending the said end portions around said supports so that they extend laterally of the coil axis.

12. Apparatus for forming filaments for electric lamps and similar devices comprising means for coiling an intermediate portion of a continuous length of wire into a compact helix with the straight end portions extending outward parallel to the axis of the coil, a die comprising separated support arms, means for gripping the coiled portion of the filament and transferring it from the coiling means to the die, a portion of the said gripping and transferring means being shaped to fit in the space between the die arms to hold the filament with its end portions extending across and beyond the sides of said die arms, nger means adjacent said die arms adapted to clamp said iilament end portions against said die arms, movable die means adapted to bend the free extremities of said filament end portions into engagement with the sides of said die arms to shape them, and means for actuating the finger means and movable die means at proper intervals.

13. In apparatus of the class described for reshaping the ends of a lament coil having straight end lportions extending outward from opposite ends of the `coil substantially parallel to the axis of the coil, a die member comprising separated support arms, means for holding a filament on said die member with its said end portions extending across said die arms and beyound 'the sides thereof, linger means Iadjacent said die arms adapted to clamp said filament end portions against said die arms, movable die means adapted to bend the free extremities of said lament end portions into engagement with thek sides of said die arms to shape them, and means for actuating the iingen'means and movable die means at proper intervals.

FRED B. IDEN.

Images