US2813327A

US2813327A - Apparatus for and method of forming and mounting supports on coiled filaments

Info

Publication number: US2813327A
Application number: US456674A
Authority: US
Inventors: Elmer G Fridrich
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1953-08-24
Filing date: 1954-09-17
Publication date: 1957-11-19
Anticipated expiration: 1974-11-19
Also published as: US2864025A; BE544825A

Description

Nov. 19, 1957 E. G. FRIDRICH 2,313,327

APPARATUS FOR AND METHOD OF FORMING AND MOUNTING SUPPORTS 0N COILED FILAMENTS Filed Sept. 17. 1954 2 Sheets-Sheet 1 LINE 4a 1774 51 1 4,42 7/ a? L za zflzsl (as A115 [1 '46 55 a2 41 3 l7 v Inventor; Elmer G. Fridrich,

Nov. 19, 1957 E. ca. FRIDRICH 2,813,327

APPARATUS FOR AND METHOD OF FORMING AND MOUNTING SUPPORTS ON CQILED FILAMENTS Filed Sept. 17. 1954 l 2 Sheets-Sheet 2 5 a 6 I I6 l5 29 26 28 24 5 74 9. 5 m 27 22 25 1 77 56 15 7 14 /3 1 6 F- 7 7 2- Elva 57 79 r Fva Elmer" G. F'rlqrich y WC V His Atto ey United States Patent Application September 17, 1954, Serial No. 456,674 14 Claims. (Cl. 29--25.13)

This invention relates to a method and apparatus for forming and mounting auxiliary supports on coiled filaments of electric heat and incandescent lamps or similar devices.

In infrared ray generating devices or heat lamps of the general type disclosed and claimed in co-p ending application Serial No. 376,042, Foote et al., filed August 24, 1953, and comprising a thin tubular quartz envelope having a coiled tungsten filament extending longitudinally therethrough, it is customary practice to provide one or more auxiliary supports for the filament at one or more points along its length to maintain the filament positioned more or less axially of the tubular envelope. Heretofore, such auxiliary filament supports have generally been in the form of wire spirals surrounding the filament, the small diameter end of the wire spiral being closed or coiled around the filament coil to thereby hold the wire spiral in place thereon. The formation and mounting of such wire spiral typesupports, however, is a slow and expensive operation, and the mechanism customarily employed for winding the wire spirals ordinarily requires considerable maintenance. Moreover, where the wire spirals are formed of tantalum, in accordance with the invention disclosed and claimed in the aforesaid co-pending Foote et a1. application Serial No. 376,042, the wire spirals are in such case subject to the disadvantage of creep, i. e., high temperature flow or distortion thereof, at the normal high operating temperatures of the lamp, resulting in the sagging of the Wire spirals with consequent sagging of the filament coil against the quartz envelope, thereby causing lamp failures.

It is an object of my invention to provide an improved and simplified method of forming and mounting auxiliary supports on a coiled filament which affords a greatly increased production rate therefor.

Another object of my invention is to provide novel apparatus for forming and mounting auxiliary supports on filament coils which apparatus is of simple character and easy to operate and requires a minimum amount of maintenance.

Briefly stated, in accordance with one aspect of my invention, a serially slit thin metal strip of tantalum or other similar highly refractory metal is inserted laterally into and between two successive coil turns of the filament coil until the filament wire enters and is trapped in the foremost slit terminating at the leading edge of the strip, after which the strip is pierced internally of the coil, by a pointed piercing mandrel inserted and movable therethrough, to form a collar-like projection on the strip engaging with the inner side of the adjacent coil turn to attach the strip to the coil, and then a stamping of the desired configuration is punched out of the strip by a hollow punch surrounding the filament coil to thereby form a filament support in situ on the filament coil.

In accordance with another aspect of my invention the serially slit metal strip is fed through a guide which guides the strip laterally into the space between a punch ICC head and a die block and into and between two successive coil turns of the filament coil which extends through the die block and the punch head and spans the space therebetween, the guide preferably being vibrated by an electromagnetic vibrator in a manner such as to assist the advance thereof into the filament coil and the entry of the wire of the filament coil into the foremost slit in the strip. The punch head is provided with a tubular punch through the hollow interior of which the filament coil extends and which, on its punching stroke and entry into the die opening of the die block,- stamps out the filament support member or disc from the metal strip positioned across the die opening. A pointed piercing mandrel, extending into the hollow punch and through the interior of the filament coil positioned therein, is movable through the filament coil to pierce the metal strip internally of the filament coil, prior to the punching of the filament support from the strip and while the strip is backed up by an anvil member inserted in the die opening, to thereby form a collar-like projection on thestr-ip which serves to fastenthe strip and eventually the finished filament support member or disc in place on the filament coil.

Further objects and advantages of my invention will appear from the following detailed description of a species thereof and from the accompanying drawing.

Inthe drawing: t

Fig. l is a plan view of apparatus comprising my invention for forming and mounting auxiliary filament supports on a coiled filament by the method of my invention;

Fig. 2 is a perspective view of the said apparatus;

Fig. 3 is a fragmentary perspective View, partly in section, of the piercing mandrel of the apparatus and its associated supporting means;

Fig. 4 is a fragmentary perspective view, partly in section and on an enlarged scale, of the metal strip guiding means of the apparatus and its associated vibrating means for feeding the metal strip therethrough;

Fig. 5 is a fragmentary sectional view of the apparatus on the line 5-5 of Fig. 1;

Fig. 6 is a fragmentary elevation of the preformed metal strip which is employed in practicing the method of my invention;

Fig. 7 is a fragmentary sectional view of the punch and die portion of the apparatus and showing the first step in the method of my invention wherein the metal strip is positioned in support-forming position in the filament coil;

Fig. 7A is a fragmentary perspective view corresponding to Fig. 7 and showing the metal strip inserted in place in the filament coil in accordance with the first step of the method of my invention;

Fig. 8 is a sectional view similar to Fig. 7 and showing the second step of the method comprising my invention wherein the metal strip is clamped in place between the punch and anvil of the apparatus;

Fig. 9 is a sectional view similar to Fig. 7 and showing the third step in the method of my invention wherein the metal strip is pierced to form a collar-like projection thereon serving to fasten the strip to the filament coil;

Fig. 9A is a perspective View corresponding to Fig. 9 and showing the metal strip fastened to the filament coil in accordance with the third step of the method of my invention;

Fig. 10 is a sectional view similar to Fig. 7 showing the fourth step in the method of my invention wherein the filament support or disc is punched out'of the metal strip; r

Fig. 10A is a fragmentary perspective view corresponding to Fig. 10 showing the filament coil and. the completed filament support or disc mounted thereon; and

Fig; 11 is a sectional view similar to Fig. 7 showing 3 the fifth and final step in the method of my invention wherein the filament coil is positioned in the apparatus so as to locate the next succeeding filament support to be formed on the filament coil in predetermined spaced relation to the last formed filament support.

Referring to the drawing, the apparatus according to the invention comprises punch means 1 for punching out a filament support of the desired configuration (herein illustrated as of circular or disc shape) from a thin metal strip 2 (Fig. 6) of a highly refractory metal such as tantalum,'tungsten or molybdenum. The punch means 1 comprises a support head or combination punch and die block 3 of a suitable metal, such as tool steel or Carboloy, mounted on a bed or base plate 4 and having a vertical cross slot'5 therein dividing the support head 3 into spaced opposed punch head and die

portions

6 and 7, respectively. The punch head and

die block portions

6 and 7 are provided with aligned equal-sized bores 8 and 9, respectively, which extend therethrough and constitute the punch opening' and the die opening of the punch means. The punch and die openings 8 and 9 are of a diameter corresponding to that of thefilament support disc to be formed, the discsin the particular case illustrated being of approximately inch diameter.

Extending into and having a close sliding fit Within the bore 8 in the punch-head portion 6 is a hollow or tubular punch member 10 in the form of a sleeve having a bore 11'of slightly larger (e. g., from .005 inch to .010 inch larger) diameter than the outside diameter of the filament coil 12 on which the auxiliary supports are to be formed and mounted,'the bore 11 being adapted to receive and support the filament coil 12 in a position extending approximately axially of the bore 8 in the punch head '6. The bore 8 is made of a length suflicient to constitute the punch head portion 6 a bearing for the punch 10 serving to align the latter with the die opening 9 in the die portion 7.

The punch 10 projects from the rear or outer side of the punch head portion 6 and it is provided at its rear or outer end with suitable punch-advancing means 13 for gradually or preliminarily advancing the punch to a forward position in which it clamps the metal strip 2 against the die face 14 of the die portion 7 as well as against a back-up anvil 53 inserted in the die opening 9. The particular punch advancing means 13 illustrated is of the manual type and comprises a hand lever 15 extending horizontally and more or less transversely of the punch 10 and pinnedto a collar 16 secured to the rear end of the punch 10 so as to swing in a horizontal plane. The hand lever 15 isprovided with a hand grip or handle portion 17 at the front side of the machine While the other or rear end of the lever is pivotally connected to a pivot block 13 pivoted on the bed 4 so as to provide, in effect, a floating pivot connection for the rear end of the hand lever 15.

Suitable punch-actuating means 19 are provided for imparting a sudden forward thrust or punch stroke to the punch 10 so as to cause it to stamp out or shear a disc from the metal strip 2. As shown, the punch-actuating means 19 preferably comprises an electromagnetic solenoid 20 mounted on the bed 4 of the apparatus and the armature 21 of which, on energization of the solenoid, is adapted to push against and pivot a horizontal actuating arm or lever 22 which extends transversely of the punch 10." The actuating or striker arm 22 is pivoted at its rear end, as indicated at 23, so as to swing in a horizontal plane. The other or front end of the striker arm 22 is forked or bifurcated to provide a pair of vertically spaced fingers 24 which span a tubular or sleeve-like rear extension 25 of the punch 10 and continuously bear against a tubular slide or hammer member 26 slidably mounted on the punch extension 25. The hammer 26 is continuously and yieldably held .in a retracted position against the forked end 24 of the punch-actuating arm 22 by a compression coil spring 28 which surrounds the punch exten sion sleeve 25 and is compressed between the collar 16 and the hammer 26. The hammer 26 is adapted to strike against the collar portion 16 of the punch 10 to deliver the punching force or stroke thereto on energization of the solenoid 20 and actuation of the striker arm 22. To permit such engagement of the hammer 26 with the collar portion 16 of the punch 10, the bore 28 of the hammer is countersunk or enIargedQas shown at 29, a suflicient distance inwardly from the striking face thereof to completely accommodate the compressed coil spring 27 therein. The energization of the solenoid 20 is controlled by suitable control means 30 which, as shown, comprises a switch 31, preferably of the type known as a microswitch, mounted on the bed 4 of the apparatus and connected in the energizing circuit 32 of the solenoid. The switch 31 is operated, in the manner hereinafter set forth, by the engagement of its control arm 33 with a tripper finger 34 carried by a horizontally reciprocable slide member 35 which is slidably mounted on thebed plate 4.

Extending through and reciprocable Within the hollow punch 10, and adapted to enter the interior space of the filament coil 12 upon insertion of the latter into'the hollow punch from the punching face end 36 thereof, is a pointed piercing mandrel 37 which is adapted to pierce the metal strip 2 internally of the filament coil 12 to form a collar-like projection 33 thereon (Figs. 9 and 9A) which serves to fasten the strip to the filament coil. The mandrel 37 extends into the hollow punch 10 axially thereof from the rear or sleeve extension end 25 thereof and it is provided with a pointed forward end 39, preferably of pyramidal or nail-pointed form, as shown in Figs. 7-11. The mandrel 37 is made of slightly smaller diameter than the inside diameter of the filament coil 12 so as to be freely slidable therethrough yet supported therein so as to position its pointed forward end 39 more or less centrally of the filament coil 12. The mandrel 37 may be made of any suitable material, e. g., hard springtemper steel mandrel wire with the pointed end 39 heattreated to maximum hardness.

Suitable operating means 40 are provided for advancing and retracting the piercing mandrel 37 and preferably, in addition, vibrating the mandrel during the interval when it is being forced through and withdrawn from the metal strip 12 tothereby assist in the piercing operation and in the withdrawal of the mandrel from the metal strip. The particular mandrel operating means 40 illustrated is of the manually operable type and comprises a horizontal hand lever 41 opposed to and adjacent the punch operating lever 15 so as to enable an operator to grip both of the

levers

15 and 41 in one hand. The mandrel operating lever 41 is pivotally mounted on the bed 4 of the apparatus, as indicated at 42, to swing in a horizontal plane, and it is connected at its rear end, by a connecting link 43, to the previously mentioned slide or carriage 35. The slide or carriage 35 is slidably mounted on the bed 4 of the apparatus for horizontal reciprocating movement in a direction longitudinally of the mandrel 37 and punch 10. For such purpose, the slide 35 is provided with a guide slot 44 which slidably receives a stationary guide bar 45 fastened to the bed 4 of the apparatus. The mandrel 37 is supported on and carried by the slide 35 so as to move forwardly or rearwardly along with the slide when the latter is advanced or retracted by the hand lever 4-1.

The mandrel 37 is supported on the slide 35', and is vibrated by an electromagnetic vibrator 46 which is suitably fastened to the slide and the vibrating armature 47 of which is coupled tothe rear end of the mandrel, as by means of a chuck 48 fastened tothe outer end of the vibrator armature and in which the rear end of the mandrel is secured or gripped. To provide additional support for the forward end portion of the relatively long mandrel 37 so as to assure the central or axial positioning of its pointed end 39 within the bore 8 of the hollow punch 10, a support collar 37' (Fig. 5) is provided on the man drel to have a sliding fit within the bore of the sleeve extension 25 on the punch 10, Also, if desired, areinforcing sleeve 48' secured in the vibrator chuck 48 may be provided for the outermost portion of the mandrel 37 to prevent the bending or doubling-up thereof during the piercing operation. The mandrel 37 and the associated slide or carriage 35 are yieldingly held in a retracted or rearward position by a compression coil spring 49 disposed within the guide slot 44 in the slide 35 and compressed between the stationary guide bar 45 and the end of the said slot 44. The operation of the vibrator 46 controlled by the closure of a switch 5% such as that known as a microswitch, which is connected in the energizing circuit of the vibrator. The switch 50 is of the normally closed typeand is maintained in an open position, when the mandrel 37 is fully retracted, by the engagement of a tripper lug 51 on the slide with the control arm 52 of the switch. Upon advance of the mandrel 37 and associated slide 35, the tripper lug 51 disengages from and releases the switch control arm 52, thereby allowing the switch 50 to close so as to energize the vibrator 46 and vibrate the mandrel 37 during its advance movement and puncturing of the metal strip 12.

For accepting the thrust of the metal strip-piercing operation by the piercing mandrel 37 and providing additional backing-up support for the metal strip during such piercing operation, an anvil or back support 53 is provided for the metal strip preferably in the form of a cylinder of steel insertable into and withdrawable from the die opening 9 and having a sliding fit therein. The anvil 53 is carried by the outer or swinging end of a more or less horizontally extending swing or support arm 54 which is fastened on a shaft 55 so as to swing in a vertical plane normal to the axis of the die opening 9. The pivot shaft 55 extends horizontally in a direction parallel to the die opening 9, and it is rotatably mounted and longitudinally slidable within support bearings 56 mounted on the bed 4. The anvil 53 is provided with a longitudinally extending V-shaped groove or slot 57 in its upper side for receiving the filament coil 12, and it is yieldably held in its forward or operative position within the die opening 9, with its anvil face 58 protruding a slight distance beyond the die face 14 (as shown in Fig. 7), by

the expansive force of a compression coil spring 59 surrounding the shaft 55 and compressed between one of the shaft bearings 56 and a collar 60 fastened on the shaft 55. The forward or operative position of the anvil 53 is determined by the engagement of a stop collar 61 on the shaft 55 with one of the bearings 56 therefor.

l On punching of the filament support disc 63 (Fig. out of the metal strip 2, the anvil 53, as well as the punched out disc 63 and the associated filament coil 12,

are pushed by the punch 10 out of the die opening 9 to a position in which the anvil is clear of the outer face 62 of the-die block 3, in which retracted position the anvil is locked by'the dropping of a pivoted locking pawl or detent 64 into a latching position wherein its swinging end 65 engages behind the forward edge 66 of the shaftreceiving collar portion 67 of the anvil support arm 54. The pawl 64, which extends more or less longitudinally of the shaft 55, is pivoted at its other end on a pivot pin or stud 68 extending from a support bracket 69 mounted on the bed 4. The pawl 64 is pivoted on the pivot pin 68 so as to swing in a vertical plane and it is yieldingly held in its lowered or operative latching position by the force of a torsion coil spring 70 surrounding the pivot pin 68 and having its opposite ends locked onto the support bracket 69 and bearing against the upper side of the latch 64, respectively. Means preferably in the form of a hand lever 71 connected to the pawl 64 are provided for releasing or swinging the pawl upwardly out of engagement with the anvil support arm 54 so as to permit the latter to be urged forwardly by the spring 59 to effect the re-insertion of the anvil 53 into the die opening 9. The pawl .64 is also provided with an anvil push-down arm 72 which, on downward swinging of the spring-loaded pawl to its lowered; or operative latching position, errgages with the upper side of and swings the anvil support arm 54 downwardly so as to carry the anvil down out of alignment with the die opening 9. A similar arm 73 on the pawl 64 extends under the anvil support arm 54 and engages the under side thereof, upon upward pivotal movement of the pawl out of its latching position by the hand lever 71, to thereby swing the said anvil support arm upwardly so as to carry the anvil 53 back into alignment with the die opening 9 and cause its reinsertion thereinto by the expansive force of the spring 59 acting on the anvil-carrying shaft 55. i Filament positioning means are provided. for locating the filament coil 12 in successive predetermined longitudinal positions within the die opening 9 in order to uniformly space the successive filament support discs 63 a predetermined distance apart on the filament coil as they are formed thereon. As shown, such filament-pg sitioning means may comprise an arm 74 extending more or less horizontally from and fastened on the anvil support shaft 55 and formed with a bifurcated or forked swinging end to provide spaced arms 75 between which the filament support discs 63 are successively positioned as they are formed to thereby locate the filament coil in position for the formation of the next filament sup.- port disc in place thereon. The two arms 75 of the filament positioning means or guide 74 are formed with upwardly opening aligned slots or grooves 76 in their upper sides for receiving the filament coil 12 therein, the said slots being aligned with the filament-receiving groove or slot 57 in the anvil 53. The portion of the filament coil 12 located outwardly of the die opening 9 and extending beyond the filament positioning guide 74 may be supported in any suitable manner, as by means of a vwshaped trough 77 for instance. The trough 77 may be suitably supported in place on the bed 4 of the apparatus.

The metal strip 12 out of which the filament support discs 63 are formed by the method and apparatus of my invention is made of a suitable highly refractory metal such as tantalum, tungsten or molybdenum having a thick ness of the order of, for example, .002 inch and a width slightly greater than the diameter of the support discs 63 to be formed. Thus, in the particular case illustrated wherein the filament support discs 63 are of a diameter of approximately inch, the metal strip 12 may be of a width of approximately 7 inch. As shown in Fig. 6, the metal strip 2 is serially slit longitudinally and medially thereof to provide successive longitudinally spaced and aligned slits 78 located approximately on the longitudinal center line of the strip. The slits 78 are each of a length approximately corresponding to the radius of the filament support disc .63 to be formed and they have corresponding flared leading ends 79 spaced apart a .distance approximately equal to the diameter of the filament support discs 63 to thereby provide, on punching out of each filament support disc from the metal strip along a line just overlapping the widest end of the flared portion 79 .of the succeeding slit 78 (as shown in dashdot lines in Fig. 6), a flared entrance or guide opening leading into the said succeeding slit for guiding the filament wire thereinto upon insertion of the metal strip 2 laterally into the filament coil 12. i l

The metal strip 2 out of which the filament support discs .63 are formed is supplied fromf a coil thereof inserted within and supported by a retaining or holderdrum 80 (Fig. 2) mounted on a support arm 81 fastened to an upstanding bracket 82 mounted .on the bed 4 of the apparatus. The drum 80 is mounted on the support arm 81 in an overhead position above thedie blockg3, and the metal strip 2 passes from the drum 80 into suitable guiding means 83 which, on advance movement of the metal strip '2 therethrough, serves to guide the metal strip into the cross slot 5 of the die block 3 and into the space between the anvil 53 and the punch .10, with the metal strip 2 disposedfiatwise across the die opening 9 and in centered relation thereto. As shown more particularly 7 'in'Fig. 4, the said metal strip guiding means. 83' comprises a pair of opposed guide plates 84 and .85 of L- shaped section between which the metal strip 2 passes and which are carried by and yieldingly held against the metal strip by a light-acting U-shaped spring 86, the two

guide plates

84, 85 together providing a guideway through which the metal strip 2 extends. The

guide plates

84, 85 may be made of any suitable material, such as nylon for instance, which will permit free and easy advance movement of the metal strip 2 between the spring-loaded guide plates.

For advancing or feeding the metal strip 2 through the guide means 83, and also assisting in the insertion of the metal strip;in place between adjacent turns of the'filament coil 12, a vibratory feeding means 87 (Fig. 4) is preferably provided for the metal strip, the said feeding means comprising an electromagnetic vibrator 88 the armature 89 of which is fastened to and supports the U-shaped spring 86 carrying the

guide plates

84, 85. The vibrator 88 is mounted on the support arm 81 in a position such that the armature 89 of the vibrator reciprocates or vibrates in alignment with the direction of sliding movement of the metal strip 2 through the

guides

84, 85. The armature 89 extends horizontally through a slot 90 in a stop member 91 mounted on the support 81, and it is arranged to strike against the bottom wall 92 of the slot 90, at the end of each advance stroke of the vibration cycle of the armature, to thereby create a sudden impact or interruptionof the advance stroke of the armature which causes the metal strip 2 in the

guide

84, 85 to be propelled or thrown a short distance forwardly in the guide by reason of its own inertia. Suitable lock means are provided to prevent rotation of the vibrator armature 89 in the vibrator such-as would cause the metal strip guiding means 83 to be swung out of its proper guiding position. The particular lock means shown comprises a catch plate 93 (Fig. 2) fastened on the support arm 81 and having a slot 94 therein through which the armature 89 extends and is snugly received to thereby lock it against rotation.

To speed up the advance movement or feed of the metal strip 2 through the

guide

84, 85 and into place within the filament coil 12 following each filament support forming operation, a pressure or back-up plate 95 (Fig. 2) for the metal strip 2 may be provided on the support arm 81, against which pressure plate 95 the metal strip 2 may be manually pressed and pushed forwardly or advanced by an operator.

In forming and mounting filament supports 63 by the method and apparatus of my invention, the anvil 53 is first inserted in and moved to its operative position within the die opening 9 and the punch 10 and piercing mandrel 37 retracted, after which the filament coil 12 is laid in the filament-receiving groove 57 of the anvil 53 and inserted in the die opening 9 as well as in the bore 11 of the punch 10 and then moved therethrough until the filament coil is in position for the formation and mounting of the first 'filament support thereon, as determined by the positioning'of the rear end of the filament coil 12 approximately opposite the locating arms 75 of the filament locating guide 74, as shown in Fig. 5. The punch 10 is then advanced, by the operation of lever 17, to bring its punching face 36, relatively close to the anvil face 58 (as shown in Fig. 7) so as to be spaced therefrom a distance slightly less than the pitch of the filament coil 12. The metal strip 2 is now advanced in the

guide

84, 85 by energizing the vibrator 88, and preferably by also manually pressing the strip 2 against the pressure plate 93 and pushing the strip downwardly, to cause insertion of the metal strip into the space between the anvil 53 and punch 10 and into the filament coil 12, between two adjacent coil turns thereof, the metal strip feeding movement being continued until the wire of the filament coil is caught in the flared end 79 of the slit 78 in the strip and is guided thereby into and bottomed in the slit 78, as shown in Figs. 7 and 7A. The punch 10 is then advanced by the operation of lever 17 to clamp the metal strip 2 firmly between the anvil face 58 and the punch face 36, as shown in Fig. 8, this clamping action of the anvil and punch serving to flatten out the portion of the metal strip disposed therebetween. With the punch 10 thus held tight against the metal strip 2 to clamp it against the anvil face 58, the piercing mandrel 37 is then advanced, by the operation of the lever 41, to cause its pointed end 39 to pierce the metal strip 2 internally of the filament coil (as shown in Fig. 9) and form or lay open a plurality of locking tongues or tabs 38 (Fig. 9A) which, because of the internal strains developed therein during the piercing operation, undergo a slight amount of outward curling which causes the tabs to partially wrap themselves around the inner side of the adjacent coil turn of the filament coil, thereby forming a collar-like projection securely locking the strip 2 onto the coil against lateral disengagement therefrom as; well as rotative movement relative thereto. During the advance movement of the piercing mandrel 37, the elec-' tromagnetic vibrator 46 which carries the piercing mandrel is energized, through the closure of its control switch 50 by the tripper lug 51 on the advancing vibrator carriage slide 35, to thereby impart vibration to the piercing mandrel which aids both in the piercing operation andin the subsequent withdrawal of the mandrel out of the metal strip. When the piercing mandrel 37 reaches its forwardmost or fully advanced position, the solenoid 20 of the punch actuating means 19 is then energized through the closure of its control switch 31 by the tripper lug 34 on the advancing mandrel carriage slide 35, thereby causing the armature 21 of the solenoid 20 to pivot the. striker arm 22 so as to drive the freely sliding hammer 26 on the punch 10 against the collar portion 16 of the punch 10 to impart a sharp blow thereto which, in combination with the continued pressure applied to the punch by the hand lever 17, serves to drive the punch 10 through the metal strip 2, against the resistance of the coil spring 27, to thereby punch out a filament support disc 63 from the metal strip 2, as shown in Fig. 10. The force of the hammer blow applied to the punch 10, together with the continued pressure applied to the punch by the hand lever 17, carries the punch completely through the die opening 9 in the die portion 7 and pushes the mandrel 53 completely out of the die opening 9. When the anvil 53 is thus pushed by the punch 10 back out of the die opening 9 and a sufficient distance therebeyond for the collar portion 67 of its support arm 54 to clear the end of the locking pawl 64, the latter is then swung down to its latching position by the action of the torsion spring 70, thereby locking the spring-loaded anvil 53 in its retracted position. Upon being thus swung downwardly into its locking position, the pawl 64, through the engagement of its anvil push-down arm 72 with the upper side of the anvil support arm 54, pushes down on and swings the anvil support arm 54 downwardly so as to carry the anvil 53 out of alignment with the die opening 9. The forming and mounting of the filament support disc 63 on the filament coil 12 being now completed, the punch 10 and piercing mandrel 37 are returned to their retracted position through the actionof the punch retracting spring 27 and the mandrel operating lever 41, respectively, so as to be in readiness for the next filament support forming operation. 7

The filament coil 12 is now withdrawn the necessary amount from the die opening 9 to position the filament support disc 63 just formed within the space between the guide arms of the filament locating guide 74 to thereby locate the filament coil 12 in proper predetermined po sition within the die opening 9 for the formation of the next filament support disc 63 thereon. By means of the lever 71, the latching pawl 64 is then raised to disengage it from behind the spring-loaded anvil support arm 54;

thereby freeing the anvil 53 for advance or return move ment thereof into the die opening 9 by the force of the spring 59. The lifting of the pawl 64 out of its latching position by the lever 71 at the same time serves to swing the anvil support arm 54 upwardly, by reason of the engagement of the anvil lift arm 73 on the pawl with the underside of the anvil support arm 54, to thereby raise the anvil 53 back into alignment with the die opening 9. Immediately uponbeing thus re-aligned with the die opening 9, the anvil 53 is forced into and advanced to its operative position within the die opening 9 by the action of the coil spring 59, so as to be in readiness for the next filament support forming operation. The operation of the apparatus from this point on, to form the next and succeeding filament support discs 63 on the filament coil 12, is then exactly the same as that described above for the first filament support disc, While I have shown and described the preferred form of apparatus according to the invention for forming and mounting the filament supports 63 in place on a filament coil 12, it will be obvious that various modifications may be made therein without departing from the invention. Thus, while the piercing mandrel 37 is shown provided with a pyramidal or nail-pointed piercing end 39, it may be provided instead with a plain conically pointed end in the case of smaller sized filament coils having an inside diameter of less than, for example, mils or so.

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

1. The method of forming and mounting a filament support in place on a coil filament which comprises, forming a thin metal strip with a slit extending inwardly from an edge thereof, inserting said strip with its slit edge first laterally into and between two successive coil turns of the filament coil, with thefilament wire inserted in and passing through said slit, and then forming and mounting the support in situ on the filament coil by inserting a pointed piercing tool through said coil from the end thereof and piercing the said strip to form a short protruding collar portion thereon engaging the inside of the coil for holding the finished support in place thereon, and punching from the strip a filament support of the desired configuration.

2. The method of forming and mounting a filament support in place on a coil filament which comprises, forming a thin metal strip with a plurality of aligned longitudinally spaced slits, with the end of the first one of said slits terminating at an edge of said strip, inserting said strip with its slit edge first laterally into and between two successive coil turns of the filament coil, with the filament wire inserted in and passing through the first one of said slits, and then forming and mounting the support in situ on the filament coil by inserting a pointed piercing tool through said coil from the end thereof and piercing the said strip to form a short protruding collar portion thereon engaging the inside of the coil for holding the finished support in place thereon, and punching from the strip a filament support of the desired configuration and overlapping the second one of said slits.

3. The method of forming and mounting a filament support 'in place on a coil filament which comprises, forming a thin metal strip with a plurality of aligned longitudinally spaced slits each flared out at a corresponding one of their ends, with the flared end of the first one of said slits terminating at an edge of said strip, inserting said strip with its slit edge first laterally into and between two successive coil turns of the filament coil to cause the filament wire to enter the flared open end of the said first slit, and then forming and mounting the support in situ on the filament coil by inserting a pointed piercing tool through said icoil from the end thereof and piercing the said strip to form a short protruding collar portion thereon engaging the inside of the coil for holding the finished support in place thereon, and punching from the strip a filament support of the desired configuration amass? 1O and just overlapping the widest portion of the flared end of the second one of the slits in said strip.

4. The method of forming and mounting disc-shaped filament supports in place on a coil filament which comprises, forming -a thin metal strip with a. plurality of aligned longitudinally spaced slits each of a length ap proximately equal to the radius of the disc to be formed, with corresponding leading ends of adjacent ones of said slits spaced apart a distance approximately equal to the. diameter of the filament support disc and with the leading end of the first one of said slits terminating at an edge of said strip, inserting said strip with its slit edge first laterally into and between two successive coil turns of the filament coil to cause the filament wire to enter the leading end of the said first slit, continuing the said lateral insertion movement of said strip into the coil until the trailing end of said first slit is positioned approximately atthe center of thefilament coil, and then forming and mounting the disc in situ on the filament coil by inserting a pointed piercing tool through said coil from the end thereof and piercingthe said strip to form a short protruding collar portion thereon engaging the inside of the coil for holding the finished disc in place thereon, and punching from .the inserted strip a disc concentric with the filament coil and just overlapping the second one of the slits in said strip.

5. The method of forming and mounting disc-shaped filament supports in place on a coil filament which comprises, forming a thin metal strip with a plurality of aligned longitudinally spaced slits each of a length approximately equal to the radius of the disc to be formed, with corresponding leading ends of adjacent ones of said slits flared out and spaced apart a distance approximately equal to the diameter of the filament support. disc and with the leading end of the first one of said slits terminating at an edge of said strip, inserting said strip with its slit edge first laterally into and between two successive coil turns of the filament coil to cause the filament wire to enter the flared leading end of the said first slit, continuing the said lateral insertion movement of said strip into the coil until the trailing end of said first slit is positioned approximately at the center of the filament coil, inserting a pointed piercing tool through said coil from the-end thereof and piercing the said strip to form a short protruding collar portion thereon. engaging the inside of the coil for holding the finished disc in place thereon, and then punching from the inserted strip a disc concentric with the filament coil and just overlapping the widest portion of the flared end of the second one of the slits in said strip.

6. Apparatus for forming and mounting a filament support member on a linear filament coil comprising a support head provided with spaced die block and punch head portions having aligned die and punch openings therethrough conforming to the configurationof the filament support member to be formed, opposed hollow punch and anvil members cooperating with and reciprocable within saidpunch and die openings respectively, said punch and anvil members having a longitudinal passageway and a longitudinal groove, respectively, for accommodating therein and supporting the filament coil in a position spanning the space between said punch head and die block portions, guide means mounted adjacent the support head to support and guide a serially slit thin metal strip into the said space between said punch head and die block portions and between two successive turns of the filament coil in said punch and anvil, with the wire of the filament coil caught in the foremost slit in the metal strip, means yieldably holding the anvil member within said die opening with its anvil face disposed approximately flush with the said die face, a pointed piercing mandrel extending through and reciprocable within both the said hollow punch and the filament coil therein to pierce the said strip and form thereon a collar-like projection located internally of and engagingthe inside of the adjacent coil a 11 turns of the filament coil to thereby fasten the strip in place on the filament coil, and means engageable with said punch to drive it forcefully through said strip and into the die opening in said die block to punch out a filament support member from said metal strip conforming to the configuration of said die opening.

7. Apparatus of the character set forth in claim 6 wherein the pointed end of the said piercing mandrel is of pyramidal-pointed shape.

8. Apparatus of the character set forth in claim 6 and comprising, in addition, an electromagnetic vibrator having its armature connected to and unitary with the said guide means for the metal strip to impart vibratory movement thereto, said vibrator being mounted on a support in a position such that the advance stroke of the vibrator armature is in the direction of advance movement of the metal strip through the said guide means, and stop means engaging with the said armature during its advance stroke to effect an abrupt interruption of the advance stroke of the unitary armature and associated guide means so as to cause the said metal strip to advance itself relative to the guide means by virtue of its own inertia.

9. Apparatus for forming and mounting a disc-shaped filament support on a linear filament coil comprising a punch head and a die block disposed in spaced opposed relation, said punch head having a punch-receiving bore therein and said die block having a corresponding bore therein aligned with said punch-receiving bore and pro viding a die opening in the die block, guide means mounted adjacent said punch head and die block to support and guide a serially slit thin metal strip into the space between the said punch head and die block and flatwise across the said die opening, a tubular punch extending through and reciprocable within the said punch-receiving bore in the punch head and having a filament coil-receiving bore therein, a strip-piercing mandrel extending axially of and reciprocable within the bore in said punch, said mandrel having a diameter less than the inside diameter of the filament coil so as to be insertable thereinto and being provided with a pointed forward end, a cylindrical anvil insertable into and withdrawable from the die opening in said die block, said anvil being reciprocable in said die opening and having a longitudinal slot in the side thereof for accommodating the filament coil therein in a position extending approximately axially of the die opening, means for yieldingly holding said anvil in place in said die block with its anvil face approximately flush with the die face of the die block, and punch-actuating means operative to engage the punch to impart a hammer blow thereto to cause it to punch out a disc from said strip.

10. Apparatus as set forth in claim 9 and comprising, in addition, a positioning guide mounted outwardly of and adjacent the said die block for receiving successive ones of the filament support discs as they are formed on the filament coil to thereby locate the said coil in predetermined position for forming and mounting the next succeeding support disc thereon.

ll. Apparatus as set forth in claim 9 wherein the said punch-actuating means comprises a solenoid having its armature provided with a striker arm portion engageable with the said punch upon energization of the solenoid.

12. Apparatus for forming and mounting a disc-shaped filament support on a linear filament coil comprising a punch head and a die block disposed in spaced opposed relation, said punch head having a punch-receiving bore therein and said die block having a corresponding bore therein aligned with said punch-receiving bore and providing a die opening in the die block, guide means mounted adjacent said punch head and die block to support and guide a serially slit thin metal strip into the space between the said punch head and die block and flatwise across the said die opening, a tubular punch extending through and reciprocable within the said punch-receiving bore in the punch head and having a filament coil-receiving bore therein, a strip-piercing mandrel extending axially of and reciprocable within the bore in said punch said mandrel having a diameter less than the inside diameter of the filament coil so as to be insertable thereinto and being provided with a pointed forward end, a cylindrical anvil insertable into and withdrawable from the die opening in said die block, said anvil being reciprocable in said die opening and having a longitudinal slot in the side thereof for accommodating the filament coil therein in a position extending approximately axially of the die opening, means for yieldingly holding said anvil in place in said die block with its anvil face approximately flush with the die face of the die block, a solenoid having its armature provided with a striker arm portion engageable with the said punch upon energization of the solenoid to impart a punching stroke to the punch, actuating means connected to said piercing mandrel for advancing it to cause its pointed end to pierce the metal strip, and control means actuated by said mandrel-actuating means, upon completion of the piercing operation by said mandrel, to energize the said solenoid and actuate the punch.

13. Apparatus for forming and mounting a disc-shaped filament support on a linear filament coil comprising a punch head and a die block disposed in spaced opposed relation, said punch head having a punch-receiving bore therein and said die block having a corresponding bore therein aligned with said punch-receiving bore and providing a die opening in the die block, guiding means. mounted adjacent said punch head and die block to support and guide a serially slit thin metal strip into the space between the said punch head and die block and fiatwise across, the said die opening, an electromagnetic vibrator having its armature connected to said strip guiding means to vibrate the latter in the direction of movement of the strip therethrough, stop means engageable with said armature during each advance stroke thereof in the direction of advance movement of the strip to effect an abrupt interruption of the advance stroke of the guide means and thereby cause the metal strip therein to advance itself through the guiding means by virtue of its own inertia, a tubular punch extending through and reciprocable within the said punch-receiving bore in the punch head and having a filament coil-receiving bore therein, a strip-piercing mandrel extending axially of and reciprocable within the bore in said punch, said man-' drel having a diameter less than the inside diameter of the filament coil so as to be insertable therethrough and being provided iwth a pyramidal-pointed forward end, a cylindrical anvil insertable into and withdrawable from the die opening in said die block, said anvil being reciprocable in said die opening and having a longitudinal slot in the side thereof for accommodating the filament coil therein in a position extending approximately axially of the die opening, means for yieldingly holding said anvil in place in said die block against movement outwardly thereof and with its anvil face approximately flush with the die face of the die block, punch-actuating means operable to actuate said punch so as to punch out a disc from said metal strip, operating means connected to said piercing mandrel for advancing it to cause its pointed end to pierce the metal strip, and control means actuated by said mandrel-operating means, upon completion of the strip-piercing operation by said mandrel, to effect the operation of the said punch-actuating means.

14. Apparatus as set forth in claim 13 wherein the said punch-actuating means comprises a solenoid having its armature provided with a striker arm portion engageable with the punch to actuate it, and the said control means comprises a switch in the energizing circuit of said sole noid and closed by the said mandrel-actuating means to thereby complete the said solenoid circuit.

No references cited.