US3154976A

US3154976A - Wire shaping apparatus

Info

Publication number: US3154976A
Application number: US137226A
Authority: US
Inventors: John A Chase
Original assignee: RCA Corp
Current assignee: RCA Corp
Priority date: 1961-09-11
Filing date: 1961-09-11
Publication date: 1964-11-03
Anticipated expiration: 1981-11-03

Description

Nov. 3, 1964 Filed Sept. 11, 1961 J. A. CHASE 3,154,976

WIRE SHAPING APPARATUS 2 Sheets-Sheet 1 j! I w g i I;

ii 124% K f; A L JMI :2 z 2 INVENTOR.

NOV. 3, 1964 CHASE 3,154,976

NV EN TOR. JZ/m A. 5/11; BY

United States Patent 3,154,976 WIRE SHAIXPJG AEPARATUS John A. Chase, Nutiey, Ni, assignor to Radio (Imperation of America, a corporation of Delaware Fiied Sept. 11, 1% Ser. No. 137,226 1i Ciaizns. (Cl. 78-13) This invention relates to apparatus for shaping the ends of wires or rods and particularly to apparatus for deburring and chamfering the ends of such wires or rods. The invention is particularly useful for forming the ends of vacuum tube support and lead-in conductors for facilitating insertion of the vacuum tubes into sockets and for forming the ends of grid electrode side rods for facilitating insertion of the side rods through mica spacer apertures.

In one type of recently designed electron tube, for example, the tube electrodes are mounted on flanges which, in turn, are mounted on support rods or conductors extending through a ceramic wafer or header member in vacuum tight relation therewith. The lead-in conductors extend sufiiciently beyond the wafer so that they may be inserted into a socket provided for the vacuum tube. The envelope of the tube is secured vacuum tight to the Wafer. For proper sealing of the conductors to the wafer, the walls of the wafer holes through which the support and lead-in conductors extend are metalized and the rods are brazed to the metal inside the holes. The holes in the wafer must fit the rods closely to provide a vacuum tight joint after brazing. The wafer is very small, being, in one example, about .400 inch in diameter, with the holes therethrough having diameters of about .017-.018 inch. Fitting the support and lead-in conductors in the holes in the water has been a difiicult, time-consuming job.

The lead wires or conductors are made from a continuous wire of molybdenum and are cut to the desired lengths. The cutting operation usually leaves a burr at the cut surface. The burr makes it diflicult to push the lead wires into and through the holes in the'wafer. Also, after the vacuum tube is completed, the burrs on the ends of the lead wires make it diflicult to insert the tube into sockets upon later use of the tube. Because of the hardness of molybdenum, undesirable wear results upon insertion of the lead wires into the corresponding holes in the sockets, particularly in tube aging and testing sockets used during manufacture of the tubes. After a relatively few insertions of the tubes into the aging and testing sockets, the contacts of the sockets are badly worn by the burrs on the lead Wires which cut away metal from the tube socket contacts. When the wires or conductors are deburred and chamfered, the fitting of the wires or conductors into the wafer during tube manufacture is easier, and socket wear due to the insertion of the tube into its socket during tube use is minimized. However, the tube leads are short, being less than about /2 inch long, and they are of small diameter, the diameter thereof being about .016 inch. Manual deburring and chamfering of such fine wires is not practical.

Another instance wherein it is desirable that the ends of wires be deburred and chamfered is in the assembly of electron tubes using wire wound grids. These grids comprise a pair of side rods about which a lateral wire is wound. In the assembly of such tubes it is usually necessary to insert the ends of the side rods through holes in mica spacers, the spacers providing support and proper relative spacings of the tube electrodes. To prevent microphonic noise producing rattle of the grid during tube operation, the side rods must fit snugly within the spacer holes. Mica is a brittle material, and if burrs are present on the side rod ends, the burrs will break oif parts of the mica and enlarge the holes thereof. Moreover,

the passage of the burrs through the holes reams the holes thereby also enlarging the holes and destroying the snug fit. It is therefore desirable to deburr the side rod ends to avoid these problems. Further, to facilitate insertion of the side rods into the holes, it is desirable to chamfer the side rod ends, the chamfered portions serving as means for guiding the side rods into the spacer holes. However, because wire wound grids are very delicate and fragile, it has been very diflicult in the prior art to deburr and chamfer the side rod ends without damaging or distorting the grids.

It is therefore an object of this invention to provide apparatus for shaping the ends of wires or conducting rods of small diameter.

Particularly, objects of this invention are to provide apparatus for deburring and chamfering the ends of wires or conducting rods of small diameter, and for doing so without damaging or distorting the devices to which the wires may be attached.

For achieving these objects in accordance with this invention, apparatus is provided which comprises a pair of dies having surfaces in slidable contact. At least one hole is provided in each die, the holes being in registry. The wire to be operated on is inserted through the hole of one die and into the hole of the opposite die. Means are provided for moving at least one die so that the axis of its hole is orbited with respect to the axis of the other hole. As will be described, the wall of the hole containing the end of the wire is so shaped that inwardly directed radial forces are applied againstthe Wire end and about the circumference thereof to mold or swage the wire end into a generally smooth surfaced, chamfered shape.

In the drawings:

FIG. 1 is a side elevation partially in section of apparatus according to this invention;

FIG. 2 is a partial plan view of the apparatus shown in FIG. 1;

FIG. 3 is a view in section, on an enlarged scale of a portion of the apparatus shown in FIG. 1 and showing details of the two dies; and,

FIG. 4 is an elevational view of an end of a wire that has been operated on by apparatus of this invention.

Apparatus for shaping the ends of wires according to this invention is shown in FIG. 1 and comprises a pair of disk-like

dies

10 and 12 having flat surfaces 13 and 13 in slidable contact with each other. A housing 15 is provided on which the two dies are mounted. Die 10 is immovably mounted on a housing top cover 17, and die 12 is mounted for movement with respect to die 10 within a die holder 29. Housing 15 is secured to a bottom cover 22, secured, in turn, to a plate 23. Details of

dies

10 and 12 and the movement of die 12 with respect to die It) will be more fully described hereinafter.

Within housing 15, die holder is rigidly secured on the end of a center rod 25, rod being rigidly secured to cover 22 by means of nuts 26. Rod 25 is flexible whereby die holder 20 and die 12 may move in a sliding or revolving fashion with respect to die 10, but not in a rotating fashion. Disposed about die holder 20 and engaged therewith through bearings 28 for imparting the desired motion to die 12 is a sleeve 3%. Sleeve 30 is rotatably mounted within housing 15 by means of bearings 32. Means are provided for rotating sleeve 30 which comprise a timing belt 34 meshed with a pulley 35 mounted on the outside of sleeve 30. Belt 34 is also meshed with a pulley 36 mounted on the shaft 37 of a driving motor 3%. Openings are provided through the side wall of housing 15 to permit passage of timing belt 34 therethrough.

As mentioned, sleeve 30 engages die holder 29 through bearings 23 mounted within sleeve 39. As shown in FIG. 1, a circular bore 42, is provided within sleeve 3% to receive bearings 28, the bearings 28 fitting against an annular shoulder 43 in the wall of bore For providing the desired motion of die 12 with respect to die it), bore 42 is disposed eccentrically with respect to the longitudinal axis of sleeve 30. This is shown exaggerated in FlG. 1 wherein the upper wall portion 45 of sleeve Stl at the right of the drawing is thicker than the sleeve wall portion 46 at the left side. Thus, upon rotation of sleeve 30 by timing belt 34, the wall of bore 452 will exert ever varying, or rotating radial forces aga nst die holder 12% through bearings 23. Since die holder in is secured to center rod 25, the die holder 2% is prevented from rotating but rather revolves or precesses about a circular orbit. The radius of precession of die holder 2% and die 12 is dependent upon the degree of eccentricity of bore 4-2, the radius selected being dependent upon the diameter of the wire being shaped, and the amount of chamfer desired.

As shown in FIG. 2, die 19 may contain a number of holes 48 therein placed to correspond, for example, with the five conductors of one type of electron tube. Die i2 has a number of holes 49 therein (only two being shown in FIG. 1) correspondingly placed with respect to holes 48. Holes 48 (FIG. 3) extend through die it), and each hole 48 has a funnehshaped section 51 adjacent the top surface 54 of die it} and a straight sided circular section 51?; adjacent the lower surface 13. The larger end of section 51 opens into surface 5 5 and has a diameter somewhat greater than that of the wires to be operated on so as to guide them into section 52 and through die 19. T e diameter of section 52 is such that the wires fit snugly therein.

Holes 49 through die 12 may also have a funnel-shaped section 56 opening into a straighosided circular section 57. The larger end of section 56 opens into the surface 13 between the dies and is in registry with hole section 52 through die 10.

In operation, wires 60 of an electron tube or grid electrode, or the like, are inserted through holes 48 of die it) and into holes 4-) of die 12 until the ends of the wires engage a portion of the tapered or inclined wall of section 56 of hole 49. The wires are pressed and maintained firmly against the wall of hole section 4% by an operator or by suitable inserting means.

Sleeve 3t? is rotated by timing belt 34, thereby imparting inwardly directed, rotating radial forces against die holder 26 and die 12, as described. The resulting effect is that die 12 slides against die 10 about an orbital path, the surfaces 1343 between the dies remaining in contact, and each hole 49 in die 12 revolves with respect to its corresponding hole 38 in die it}. The inclined wall of each hole section 56 of the constantly processing die 32 engages one circumferential portion of the wire 6% therein during each instant and successive circumferential portions at sucecding instants. The inclination of the wall of section 56 and the fact that the ends of the wires 60 are pressed thereagainst results in inwardly directed radial force being applied to the wire ends. These forces smooth the ends of the wire 69, and mold and press them into the chamfered shape shown in PEG. 4.

The molding and shaping forces, it is noted, are applied uniformly and constantly against the wire ends. Since the wires 69 are held snugly within hole sections 52 of die 10, the molding forces do not affect the devices to which the Wires may be attached. Hence, fragile devices such as wound grids may be operated on by apparatus of this invention.

Hole sections 57 within die 12 are provided to collect the metallic particles which may be rubbed off the ends of the wires. The wires, it is noted, are not cut, but rather molded or swaged into shape, and the amount of collected particles is not excessive. Apertures in die holder 26 (not shown) may also be provided communicating with hole sections 57 for collecting the particles. By these means the apparatus need not be frequently shut down for cleaning purposes.

Molybdenum is a hard material, as mentioned, and to prevent rapid wear of die 12, die 12 may be made of a very hard material, such as an alloy of tungsten carbide and cobalt, known commercially as Carboloy.

While it is clear that more or less forming

holes

48 and 49 may be provided through the dies 18 and 12, five wire forming holes are shown in FIG. 2. If only one centrally located shaping hole is provided in each of the dies, it is not necessary to prevent the dies from rotating with respect to each other since with only one pair of holes so placed, a radially inward forming force of ever changing direction will result whether the dies rotate about the axis or not. However, when one or more off-center pairs of forming holes are provided in the dies, as here shown and described, the dies are arranged to be substantially rotational with respect to each other, with one die having a kind of orbiting or precessing, but not rotating, motion with respect to the other. Hence, the forming forces are still directed substantially radially for wires in each of the pairs of holes in the dies, that is, towards the center of each wire and always at different points around the circumference of each wire.

What is claimed is:

1. Apparatus for chamfering the end of a wire comprising a housing, a die fixedly mounted in said housing, a second die slidably mounted in said housing, said dies having a face-to-face contact, .here being a wire receiving hole through each of said dies, one of said holes having a funnel-shaped section for charnfering the end of a wire therein, and means for moving said slidably mounted die with respect to said fixedly mounted die in an orbital path for causing the tapered Wall of said funnel-shaped section to en age successive peripheral portions of the end of said wire therein.

2. Apparatus for shaping a wire comprising a housing, a die fixedly mounted in said housing, a second die slidably mounted in said housing, said dies having face-toface contact, there being a wire receiving hole through cach'of said dies, the wall of one of said holes being funnel shaped and of such dimensions for receiving the end of a wire in substantially point contact therewith and for exerting an inwardly directed radial force against said wire end, and means for processing said slidably mounted die with respect to said fixedly mounted die while maintaining the faces of said dies in contact for causing said wall to engage successive peripheral portions of the end of said wire.

3. Apparatus for shaping a wire comprising a housing, a die fixedly mounted in said housing, a second die slidably mounted in said housing, said dies having face-toface contact, there being a wire receiving hole through each of said dies, the hole in one of said dies having a funnel-shaped section for shaping a wire received therein, the large diameter end or" said funnel-shaped section opening into the contacting faces of said dies, the other of said holes being straight sided and having a diameter for snugly receiving and supporting a wire to be shaped, and means for moving said slidably mounted die with respect to said fixedly mounted die about an orbital path.

4. Apparatus for forming a conductor to provide a conductor with a smooth, chanrfered end, said apparatus including a housing, a pair of dies in said housing having oppositely disposed fiat surfaces in contact with each other, said dies being provided with registering holes extending therethrough normal to said flat surfaces for receiving a conductor to be formed, one of said holes having a funnel shaped section extending outwardly into said surfaces for engaging a peripheral edge portion of a conductor inserted into said holes, one of said dies being fixed in said housing and the other of said dies being slidable with respect to said one die, and means within said housing and connected to said slidable die for causing the hole within said slidable die to follow an orbital path with respect to the registering hole in the fixed die.

5. Apparatus for forming a conductor to provide a conductor with a smooth, chamfered end, said apparatus including a housing, a pair of dies in said housing having oppositely disposed flat surfaces in contact with each other, said dies being provided with overlapping but misaligned holes extending theretl'n'ough normal to said flat surfaces for receiving a conductor to be formed, one of said dies being fixed in said housing and the other of said dies being slidable with respect to said one die, the wall of one of said holes tapering inwardly away from said flat surfaces for engaging an end edge portion of said conductor inserted through the other of said holes and into said one hole, and means within said housing and connected to said slidable die for causing said slidable die to follow an orbital path with respect to the overlapping hole in the fixed die while maintaining said fiat surfaces in contact.

6. Apparatus for deburring and charnfering the end of a Wire comprising a housing, a pair of disk-like dies mounted on said housing and having oppositely disposed flat surfaces in contact with each other, said dies being provided with overlapping but misaligned holes extending therethrough normal to said flat surfaces for receiving a wire, one of said dies being fixed in said housing and the other of said dies being mounted on resilient means permitting slidable movement of said other die with respect to said one die, and rotatable means within said housing having an eccentric coupling with said slidable die for causing said slidable die to precess with respect to said fixed die, the hole in said slidable die having a funnel-shaped section for shaping a wire therein, the larger end thereof lying in the flat surfaces of said dies.

7. Apparatus for deburring and chamfering the end of a wire comprising a housing having a pair of dies therein, one of said dies being fixedly mounted on said housing and the other of said dies being mounted therein for movement with respect to said one die, said dies having oppositely disposed flat surfaces in contact with each other, and means for sliding said other die in an orbital path with respect to said one die, said means including flexible support means secured to said other die permitting revolution of said other die but not rotation thereof, rotatable means having a bore therein eccentric to the axis of rotation of said rotatable means, the wall of said bore being disposed about and rotatably engaged with a portion of said support means, and means for rotating said rotatable means, and each of said dies having a hole extending therethrough and normal to said flat surfaces, said holes being in registry, and the hole in said other die having a funnel-shaped section, the larger end of said section opening into said flat surfaces.

8. Apparatus for deburring and chamfering the end of a wire comprising a housing having a pair of dies therein, one of said dies being fixedly mounted on said housing and the other of said dies being mounted therein for movement with respect to said one die, said dies having oppositely disposed flat surfaces in contact with each other, and means for sliding said other die in. orbital path with respect to said one die while maintaining said surfaces in contact, said means comprising a flexible support rod secured to said other die permitting revolution of said other die but not rotation thereof, a rotatable sleeve having a bore therein eccentric to the axis of rotation of said sleeve, the wall of said bore being disposed about and rotatably coupled to said other die, and means for rotating said rotatable sleeve, and each of said dies having a hole extending therethrough and normal to said flat surfaces, said holes being in registry, the hole in said other die having a funnel-shaped section, the larger end of said section opening into said flat surfaces, and the hole in said one die having a straight-sided section also opening into said flat surfaces.

9. Apparatus for shaping a wire comprising a housing having two dies in sliding contact therein, means for moving one die with respect to the other in such manner that the axis of one die revolves with respect to: the axis of the other die, a wire receiving hole in each die, the Wall of one of said holes being so shaped as to exert a rotating inwardly directed radial force against successive peripheral portions of a Wire in contact with said wall when said one die is moved in said manner whereby the edge of said wire is chamfered.

10. Apparatus for shaping a wire comprising a first fixed die, and a second die slidably mounted with respect to said first die, said dies having contacting. surfaces, one of said dies having a straight sided wire receiving hole extending therethrough for receipt of a wire therein in snug supported fit, an overlapping but misaligned opening in the other of said dies, said opening being funnel shaped and expanding outwardly into said surfaces for engaging a peripheral edge portion of a wire inserted through said hole and into said opening, and means for moving said slidable die with respect to said first die for causing said hole and said opening to orbit with respect to one another and for causing said funnel shaped wall to progressively engage successive edge portions of said wire within said opening.

References Cited in the file of this patent UNITED STATES PATENTS 663,998 McCabe Dec. 18, 1900 740,492 Veeder Oct. 6, 1903 1,265,345 Rock May 7, 1918 1,635,807 Amberg July 12, 1927 1,657,295 Bark Jan. 24, 1928 2,038,255 Worthington Apr. 21, 1936 2,794,303 Wickes June 4, 1957 FOREIGN PATENTS 1,091,453 Germany Oct. 20, 1960

Claims

1. APPARATUS FOR CHAMFERING THE END OF A WIRE COMPRISING A HOUSING, A DIE FIXEDLY MOUNTED IN SAID HOUSING, A SECOND DIE SLIDABLY MOUNTED IN SAID HOUSING, SAID DIES HAVING A FACE-TO-FACE CONTACT, THERE BEING A WIRE RECEIVING HOLE THROUGH EACH OF SAID DIES, ONE OF SAID HOLES HAVING A FUNNEL-SHAPED SECTION FOR CHAMFERING THE END OF A WIRE THEREIN, AND MEANS FOR MOVING SAID SLIDABLY MOUNTED DIE WITH RESPECT TO SAID FIXEDLY MOUNTED DIE IN AN ORBITAL PATH FOR CAUSING THE TAPERED WALL OF SAID FUNNEL-SHAPED