US2873835A - Lead wire feeding device - Google Patents

Description

Feb. 17, 1959 P. w. MAURER ETAL LEAD WIRE FEEDING DEVICE 2 Sheets-Sheet 1 Filed Sept. 26, 1957 INVENTORS PIE/F1?! 0141144045? 6 HEA/m Z. 5.44/57- P. W. MAURER ET AL LEAD WIRE FEEDING DEVICE Feb. 17, 1959 2 Sheets-Sheet 2 Filed Sept. 26, 195? 11v VEN T0125 P/E/FAE 144/144 0mm 5 HENRY A. 5.4 057' By a A 7- TUBA/5) United States Patent LEAD WIRE FEEDING DEVICE Pierre W. Maurer, Nutley, and Henry L. Blust, Lyndhurst, N. J assignors to Radio Corporation of America, a corporation of Delaware I Application September 26, 1957, Serial No. 686,332

7 Claims. (Cl. 193-2) This invention relates to apparatus for handling wire members and particularly to apparatus for feeding a plurality of predetermined length lead-in wires to a stem mold in the fabrication of button-type electron tube stems.

In the manufacture of certain electron tubes, a button type stem structure is prefabricated for subsequent sealing to a tubular glass member to provide an electron tube envelope. Such a stem structure may comprise a glass disk with a plurality of wires sealed therethrough in a circular boundary. Fabrication of such a stem is performed on a turret type machine having a plurality of stations positioned around and adjacent the periphery thereof. At one station the plurality of short length leadin wires is deposited on a mold onto which is subsequently placed a cylindrical glass member to be formed into the aforementioned disk. The several lead-in wires are dropped by a separate wire handling device into a member having a plurality of tapered chutes which direct the wires upon the mold. However, in prior art lead wire feeding devices, much difficulty has been encountered due to jamming of distorted lead wires in the chutes. Such jamming results in the entire machine having to be shut down to clean out the jammed wires thus greatly reducing the stem machine efficiency.

It is therefore an object of our invention to provide improved lead wire feeding apparatus which is not subject to the aforementioned jamming problem of the prior art.

Generally, according to our invention, apparatus for feeding lead wires comprises a longitudinally slotted frustoconical core seated in a mating core housing. A plurality of chutes are thus provided for directing lead wires inserted therein onto a mold. The core housing member is split such that the split portions thereof can be pivoted away from the slotted core to effectively open the sides of the chutes thus permitting any distorted wires which might be jammed therein to fall free.

In the drawings:

Fig. l is a side elevation partly in cross section of lead wire feeding apparatus according to our invention;

Fig. 2 is a cross sectional View taken along line 2-2 of Fig. 1;

Fig. 3 is an exploded perspective view of the chute and split nozzle portions of the apparatus of Fig. 1;

Fig. 4 is a side elevation view of the plunger assembly disposed below the lead wire feeder and adapted for ice cooperation therewith. Although shown in proper relative disposition, for the sake of simplicity of description, no inner-connecting mounting means of the aforementioned apparatus is shown. In operation, the turret table 16 is fixedly mounted in a vertical orientation but is adapted for rotation about a central vertical axis 17 as indicated by the arrow; the plunger assembly 14 is mounted in a fixed position; and the chute-and-nozzle assembly 12 is fixedly mounted laterally but is adapted for vertical movement upward against the plunger assembly 14 and downward into seating relationship with a mold jig 18 as indicated by the arrows. Figs. 2, 3, and 4 in conjunction with Fig. 1 best show the detail assembly of the chute-and-nozzle and plunger assemblies according to our invention.

In Fig. 3 the chute-and-nozzle assembly 12 is shown in exploded perspective to include a slotted frusto-conical core 26 adapted to be supported by means such as a first core housing 22 and seated in a second core housing or split housing 24. For the sake of'clarity and brevity these housing members will hereinafter be referred to respectively as simply the core housing 22 and the nozzle housing 24. With the slotted core 20 seated therein, a plurality of tapered chutes 26 are thus provided. These are best shown in Figs. 1 and 2. As such, one wall portion 28 of each chute 26 is provided by the inner walls of the core housing 22 and the nozzle housing 24. The slotted 20 is dimensioned to seat in the core housing 22 and in the nozzle housing 24 with the large end 30 of the core 20 flush with the corresponding end of the core housing 22 and with the small end 32 of the core 20 slightly recessed within the nozzle housing 24, as shown in Fig. 1. A top cap 34 is provided which has a series of apertures 36 therethrough, with each aperture aligned with one of the slots 38 of the core. The cap 34 is adapted to be attached to the slotted core 20 by a machine screw 40; and the slotted core 20 is in turn fixed in the core housing 22 by a set screw 42.

The split nozzle housing 24 comprises two similar mating nozzle pieces 44 each including a flat plate portion 46 and an internally tapered core receiving portion 48. Each nozzle piece 44 is pivotally attached to the core housing 22. by a screw 50. Each of the two nozzle pieces 44 carries a peg 52 at the end opposite its screw 50 to which one end of a coil spring 54 is connected. The coil spring 54 urges the nozzle pieces 44 toward each other and around the end portion of the slotted core 20. Thus, the core receiving portions 48 of the nozzle pieces 44 serve as a continuation of the core housing 22 to provide a continuation of the chutes 26. The plate portions 46 of the nozzle pieces 44 are cut away at their inner adjacent edges 55 next to their mounting screws 50. This enables the nozzle pieces 44 to be spread apart by pivotal motion about their mounting screws 50. Also, in order toprovide clearance for the pivotal movement, either the side of the core 26 facing the pivot screws 50 or the inner corners 56 (Fig. 5) of the nozzle pieces '44 in contact therewith, must be cut away. This is necessary since the corners 56 of the nozzle pieces 44, in being pivoted away from the core, first move slightly into the core. This is'caused by the fact that the pivots 50 and the corners 56 are not on the same radial line of the core 20. Figs. 1, 3 and 5 show the core 20 with a cut-away portion 57 where the corners 56 of the nozzle pieces 44 would otherwise contact. Alternatively, of course, the corners 56 themselves could be beveled off. The plate portions 46 are also provided with a V-bevel 58 at their contiguous edges on their upper surfaces of the other end thereof for cooperation with the plunger assembly apparatus 14 as will hereinafter be described. The extending'en'd of the core receiving portions 48 of the nozzle housing 24 is provided with a slight counterbore 62 to enable a seating indexing with the mold jigs 18 on the turret table.

In Figs. 1 and 4, the plunger assembly 14 is shown to comprise a wedge plunger 62 having a V-nose 64 which is longitudinally slidable in a plunger housing 66. A first pin 68 is attached to the upper end 70 of the wedge plunger 62 and a second pin 72 is attached to the lower end 74 of the plunger housing 66. A coil spring 76 connected between the two pins urges the wedge plunger 64 downward to where a stop-ledge 78 on the upper end thereof contacts the plunger housing 66.

In the fabrication of a button stem the entire chuteand-nozzle assembly 12 is first lowered down upon one of the mold jigs .18 indexed therebeneath such that the mold jig is situated in the counter-bore 62 of the nozzle housing 24. A lead wire dispensing device (not shown) then places one wire in each of the apertures 36 of the top plate 34- of the lead wire feeder 10 where they are free to fall down the chutes 26 and onto the mold jig in a spreading apart of the nozzle pieces 44 from each other. At this point the chutes 26 have been opened to permit any distorted lead wires which might have been placed therein to be ejected, thus preventing jamming during the succeeding wire feeding operation. The opening clearance afforded between the core 20 and the nozzle pieces 44 is best illustrated by Fig. as shown in solid lines. By contrast, a closed position of the nozzle pieces 454 is shown in phantom in the same figure. The resistance to spreading of the nozzle pieces 44 by the coil spring 54 attached thereto is less than the resistance provided by the coil spring 76 to an upward slidable movement of the wedge plunger 64. This results in the nozzle pieces 44 spreading away from the slotted core 20 rather than the wedge plunger sliding within its housing. However, the spring biased slidable operation of the wedge plunger serves as a safety measure against machine damage should the nozzle pieces 44 be frozen against pivotable movement.

With reference to Figs. 1-5, our invention has been described and illustrated as applied to the production of button-type stems as used in the fabrication of the conventional seven-pin miniature electron tube. Although our invention proves most advantageous in such an ap plication as this, where relatively fine, easily distortable lead-in wires are used, it nevertheless is not limited to the specific form illustrated.

Fig. 6 illustrates a modified embodiment of the split nozzle portion of our invention which is better suited for production of 8 pins stems. Also, an alternative means of providing the pivotal movement to the nozzle pieces is illustrated.

A single pivot split nozzle 80 of Fig. 6 might simply be substituted for the split nozzle 24 of Figs. 1 and 3. Like its counterpart, the split nozzle 80 is adapted to receive the lower end of a slotted frusto-conical core 90 and to be pivotally removed therefrom. The split nozzle 80 comprises two nozzle pieces 82 and 83 which are pivotally mounted in a split bearing arrangement 84 about a single pivot screw 86. Since the pivot 86 lies on the split line 88 of the two nozzle pieces 82 and 83, the clearance problem of the split nozzle assembly 24 discussed in reference to Fig. 5 is non-existent. Thus, neither the core 90 nor the corners 92 of the nozzle pieces 82 and 83 needbe cut away. As such, the single pivot nozzle 80 is better suited for production of stem designs where a lead-in chute 94 must be provided at the point where the nozzle piece corners 92 contact the core 90.

Each of the nozzle pieces 82 and 83 is provided with an arm 96. The arm 96 of one nozzle piece carries an arcuate cylinder 98, and the arm 96 of the other nozzle piece carries a coperating piston 100. A coil spring 102 urging the nozzle pieces 32 and 83 together is stretched between the two arms 96. A source of air pressure (not shown) can be connected to the cylinder 98 for providing a means of spreading the nozzle pieces 82 away from the core 90.

It will be appreciated that either the single pivot nozzle apparatus or the piston-cylinder apparatus 98100 can be independently incorporated as a portion of our lead wire feeder invention.

For purposes of simplicity of description, our invention has been illustrated in two of its simplest forms. In actual practice however, various design features might be modified in order to better adapt our invention to specific turret machine apparatus. General shape of the constituent parts and specific assembly thereof can be modified without departing from the scope of the invention. For example, in one specific application, in order to provide easy assembly and disassembly, it has been found expedient to divide the chute-and-nozzle assembly of Fig. 1 into two separate sections generally along the horizontal plane containing'the section line 2-2 as shown in Fig. 1. The separate sections are then assembled with a tongue and groove arrangement.

Other modifications will be readily suggested to one skilled in the art without departing from the spirit of our invention.

We claim:

1. A lead-in wire feeder comprising an elongated core having a plurality of longitudinal slots around the peripheral surface thereof, means supporting said core, and a housing receiving said core, said housing being split into two parts along a plane generally longitudinal to said core, each part being pivotally mounted relative to said core for pivotal movement away from said core.

2. Lead wire feeding apparatus comprising a generally frusto-conical core longitudinally slotted around the peripheral surface thereof; means supporting said core; a housing member dimensioned to receive said core, said housing member being divided into two pieces along a longitudinal diametric plane of said core, said housing pieces being pivotally mounted relative to said core and adapted to be pivoted away from said core; and means for effecting pivotal movement of said housing pieces.

3. Wire handling apparatus comprising a frusto-conical core having a plurality of tapered longitudinal slots around the periphery thereof, first means supporting said core, a pair of housing members abutting each other along a plane of abutment and each having a semi frustoconical recess therein, corresponding parts of said recesses facing each other and constituting a frusto-conical cavity adapted to receive said core in seatable relationship, said housing members being pivotally mounted relative to said core for movement away from said core, and second means for effecting said movement.

4. Wire handling apparatus according to claim 3 wherein said second means comprises a wedge plunger adapted to contact said housing members at their plane of abutment and to spread said members apart.

5. Wire handling apparatus according to claim 3 wherein said second means comprises an air piston-and-cylinnozzle housing member and adapted for insertion be tween said nozzle housing portions to effect said arcuate movement.

7. Apparatus for handling wire lengths comprising a spring biased wedge plunger and a chute-and-nozzle assembly mounted adjacent thereto and movably adapted for engagement therewith, said chute-and-nozzle assembly including a frusto-conical core having a plurality of longitudinal slots disposed around the periphery thereof, a core housing having a tapered aperture therethrough seatably receiving said core, a nozzle housing having a 10 ment.

No references cited.

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