US2988254A - Mechanical lead breaker - Google Patents

Description

y June 13, 1961 R. K. FULGER 2,988,254

MECHANICAL LEAD BREAKER Filed June 4. 1959 3 Sheets-Sheet 1 wAFE/JAwS4 NEARCHUCK CAM /56 WAI-'Efe JAWS /A/ w/AE BREAK-@FF P05/wmv JNVENTOR.

AT OSCI LA E0 CAM (06 A TTORNE Y June 13, 1961 R. K. FULGER 2,988,254

MECHANICAL LEAD BREAKER Filed June 4, 1959 Y 3 Sheets-Sheet 2 U "7' n www ff C MAD Q j 4 Q Qi?? @L '/4 f/Z i INVENTOR. z5 LJ /LI U Ll 20 LIU Rufel K Bagger /6 "ma BAW BY 5 UNM/m l (75g/; i)

m6 /56 6 /y ra@ A MEN June 13, 1961 R. K. FULGER MECHANICAL LEAD BREAKER 3 Sheets-Sheet 3 Filed June 4, 1959 INVENTOR. Rwell IC F BY @er ATTORNEY Patented June 13, 1961 2,988,254 MECHANICAL LEAD BREAKER Russell K. Fulger, Mill Hall, Pa., assgnor to Sylvania Electric Products Inc., a corporation of Delaware Filed June 4, 1959, Ser. No. 818,192 9 Claims. (Cl. 22S- 97) This invention relates to mechanism for breaking off part of a wire from a component forming part of an electron tube, during the manufacture of said tube.

ln the manufacture of some types of electron tubes, it is necessary to provide a stem to form part of the tube, said stern being comprised of a disc like glass wafer and a number of lead-in Wires traversing the wafer and extending beyond both faces of the wafer. Some of these Wires, in the completed tube are connected to electrodes within the tube `and extend exteriorly of the completed tube to be plugged into a socket for connection of the electrodes with contacts in the socket. Where the number `of such lead-in wires is small and therefore fail to aiord suiiicient support for parts within the tube, it has been customary to imbed within the wafer additional wires or dummy leads to help support the parts and these leads do not extend exteriorly of the completed tube.

In one form of dummy lead, disclosed in the patent to Cresswell and Schnering 2,892,008, the wire is of such form rand of such length that initially it extends from both faces of the wafer, but, prior to the tube being completed, the part of each lead-in Wire of the dummy leads which would otherwise extend exteriorly of the tube is snapped off ilush with the base to prevent accidental connection of circuit wires to the dummy leads.

In the application of Miller and Weaver led May 6, 1959 `and bearing Serial No. 811,342, now Patent No. 2,970,731, there is disclosed a form of mechanism for automatically snapping oif the excess portion of the dummy leads as the stems are fed from a conveyor into chucks on a stem wire cutting and bending machine. In the form of invention disclosed by Miller and Weaver it was necessary to provide each chuck with a breaker unit or breaker units to assist in the snapping olf operation and therefore a considerable number of such units were necessary to ll all the chucks. Moreover whenever the number or position of .the dummy leads in a stem was changed, it was necessary to change the units in all of the chucks.

It is an object of this invention to provide a single breaker device which when attached to a stem conveying machine provided with chucks for the stems will operate successively on the stems to snap olf excess portions of selected lead-in wires as they are brought to the station at which the breaker device is located.

It is a further object of the invention to make the device of such character that it lends itself easily to change in the number of lead-n wires to be snapped off and to diiferent positions of these wires in the stems.

These objects will be better understood and others will become apparent upon consideration of the following specification when taken in conjunction with the accompanying drawings in which:

FIG. l is a fragmentary front elevation of the machine.

FIG. 2 is a section on the line 2-2 of FIG. 1, in part showing a side view of the breaker mechanism.

FIG. 3 is a view looking in the direction of the arrows in FIG. 1, showing, in part, a top view of the breaker mechanism.

FIG. 4 is a section through the breaker mechanism on the -line 4 4 of FIG. 3.

FIG. 5 is a section on the line 5 5 of FIG. 4, in the manner showing a spider support for one or more breaker fingers.

FIG. 6 is a fragmentary portion of that: which is shown in FIG. 5 showing a pair of spreading rollers for Wafer grasping jaws in a shifted position from that shown in FIG. 5

FIG. 7 is a diagrammatic view showing the association of drive between the chuck conveyor and the breaker device.

FIG. 8 is a view of a stem formed by the breaker, and

FIG. 9 is a timing chart of the breaker mechanism.

Now referring to the drawings in greater detail, in FIG. 7 there is disclosed in diagrammatic form an endless chain conveyor 10, carrying equally spaced chucks 12, the conveyor passing around an idler gear 14 and a driven gear 1.6. The driven gear is intermittently operated by any conventional intermittent drive mechanism as a motor 18 and intermediate Geneva drive 20. The chuck, to be described in greater detail, may be loaded with articles at the loading station 22 by any conventional mechanism, or by hand, and as the anticles are indexed around with the chain several operations may be performed thereon at various stations 23 along the conveyor chain. Since these operations form no part of the invention, no further description Ithereof is necessary.

At a selected station indicated as breaker station 24, the anticle, here an electron tube stem, is treated by the breaker device of the invention, and subsequently the stem is unloaded from the chuck, as at station 25.

One form of stem, `as formed by the breaker device, is illustrated in FIG. 8. It comprises a disc wafer 26 of glass provided with a long glass tubu'lation 28 subsequently used for evacuating the electron tube, and a number of lead-in wires, known as Dumet wires. There are two types of these wires as explained in detail in the patents to Cresswell et al. and in the application to Miller et al. The type indicated as 3l) has a reduced in diameter intermediate section with the intermediate section and portions of both adjoining larger in diameter sections embedded in the glass wafer. A second :type 32, has a reduced in diameter intermediate section but it is embedded in the wafer in such a fashion that the joint between the intermediate section and an adjoining thicker section is liush with the glass surface to permit easy breaking off of the lead-in wire at the liush joint. FIG. 8 shows a stem with a broken-off lead to leave the dummy lead, later utilized along with the iirst type of Dumet leads, to support parts inside of the electron tube. The Wires extending to the right of the wafer in FIG. 8 are later used for electrical connection with `a tube base or with socket contacts. Although the wires to the left of the Wafer in FIG. 8 are, for the sake of simplicity, shown as straight, in actuality, when processed by the wire bending and cutting mechanisms at the various stations 23, they may be of various lengths and variably bent. The wires remaining to the right of-,the wafer, however, are all straight.

The stem, as stated heretofore, is suitably inserted into a chuck 12 at the loading station. The chuck is described in detail in the Miller and Weaver application previously referred to and is shown in less detail here in FIG. 4. It comprises, in general, a body 34 having seated thereon a collar 36 against which is pressed a spacer ring 38 by a nut 48 threaded on the end of a chuck stem 42, the opposite end of the stem being flanged and having perforations 44 to receive the lead-in wires 30` and 32, there being aligned perforations 46 in the collar 3|6 to receive the wires. The under surface of the liange is provided with radial holes 50 in which there rides balls 52 normally obstructing the perforations 46 by reason of pressure against the balls by an internally bevelled chuck ring 54, the ring being pressed upwardly by springs 56 spaced circularly below the ring. Besides the chuck stem receiving the lead-in wires, it also has an axial through opening '58 for loosely receiving the exhaust tubulation.

At the loading station, a stem is inserted in the chuck by depressing the chuck ring against the action of the springs 56, the tubulation then being received in the opening; 58 and the lead-in wires in the perforations 44 and 46, with the stem thrust into the chuck as far as it will go.

As the breaker station, at which the dummy lead is to have part of its wire snapped oi, the stem is withdrawn to the dotted line position shown in FIG. 4. In this position the exhaust tubulation 28 is still within the opening 58, though this is not essential, while the leads 30 and 32 `are wholly withdrawn from `the chuck. When withdrawn, the part of 'the wire 32 to the right of the Wafer in FIG. 4 will be snapped off by a mechanism indicated generically as 60 and then the stem will be reinserted in the chuck.

Part of the breaker device is fixed on a platform 62 bolted to the machine. On this platform is fastened an angle bracket 64. To a vertical face of this bracket is fastened a cam support 66, as by screws 68. The front face of the support is recessed as indicated at 70 for a reason soon to be apparent, and fastened to the front face of the support by bolts 72, is a cam ring 74 provided with arcuate slots 76 through which the bolts pass to provide for arcuate adjustment of the ring. Thus ample leeway for positioning of the wire flick off fingers with respect to the wires on a stem is provided. The inner arcuate surface of the cam ring is undulated or scalloped as shown at 78.

The support is also provided with a horizontal bearing 80. Journalled Within the bearing is a tubular sleeve 82 .provided integrally at its forward end with a spider 84 resting against the forward end of the bearing 80 and provided with pairs of parallel ears 86 extending chordally of the spider. Fastened to the rear end of the sleeve, see FIG. 1, and bearing against the rear end of bearing 80 is a spider operator crank 88 connected by a pitman 90 to Ia bell crank 92 pivoted on the bracket 64, the bell crank being connected by a lthrust rod 94 to a rocker lever 96 pivoted on a pivot shaft 98 fixed in bearingsl 100 mounted on a base plate 102 of the machine and provided with a follower roller 104 riding on a cam 106 fastened to a cam shaft 108 mounted in bearings 107. The shaft 108 is connected by suitable connections with the motor 18.

Pivotally mounted between any selected pair of ears 86 is a lever 110, the same being pivoted on a pin 112 between the ears and provided on its rear end with a roller 114 bearing against the undulatory cam surface 78 of the cam ring 74 with part of the roller land its supporting pin extending into the recess 70. The forward end of the lever is provided with a flick finger 116 extending perpendicularly to the lever 110 and toward but normally slightly in advance of a lead-in wire 32 to be flicked off. When the lspider 84 on sleeve 82 is oscillated by operation of the crank 88 and associated mechanism, the roller 114 will ride from a high point on the bam to a low point. A spring 118 will then urge the ilick finger into the circle of lead-in wires 30, 32 and will flick off the lead 32 as the sleeve is oscillated. If more than one dummy lead-in wire is to be treated, then additional levers 110 and fingers 116 will be pivoted by the chordal pairs 86 of the spider fand oscillation of the sleeve 82 will then flick olf more than one wire 32.

shaft 134 supported at the forward end in a force fit bushing 135. On the forward end of the shaft is pinned a roller yoke 136 carrying a pair of pivot pins 138 each carrying a roller 140. When the shaft 134 is oscillated, the rollers will engage the interior faces ofthe jaws and force them apart as shown in FIG. 6. The rear fa'ce 141 of the yoke bears against the front face of axle 120 and the bushing 135.

'Ilhe axle 120 and shaft 134 are reciprocated rectilinearly, as a unit, toward and from a stem holding lchuck 12, in order that the jaws may grasp a stem in lthe chuck, withdraw it for flick oif of the dummy lead-in wire, and again replace the stem in the chuck. To guide the parts in their rectilinear movement and without rotation of the jaws, the axle 120, at its rear end, see FIGS. 1, 2 and 3, is provided with a flat portion 142 against which is secured a vertical key 143 riding in a keyway 144 in an arm 146 bolted to a vertical face of the bracket 64. To reciprocate the same pants, the axle 120, see FIGS. 1 and 3, has pivoted to the rear end thereof a pitman 148 connected to the vertical arm of a bell crank 150 whose horizontal arm is connected via la Vertical thrust rod 152 to a horizontal rocker lever 154 pivoted on the countershaft 98 and having a cam follower roller resting on a cam 156 fast on the cam shaft 108. Rotation of the cam 156 will affect translatory movement of the jaws and the jaw opening and closing mechanism while the jaws are guided by the key 143 riding in the slot in arm 146.

To rotate the shaft 134, the rear end thereof has fas tened thereto an arm 158, close to the rear fa'ce of the 'axle 120 to prevent axial shift of the shaft 134 and the roller yoke 136 fixed thereon relative to the axle. The arm is oscillated by a thrust rod 160 having universal joint connection with the arm and a rocker lever 162, pivoted on the countershaft 98 and having a cam follower roller resting on the cam 164 fast on the cam shaft 108. The universal joints allow for the translatory movement of the shaft 134 and axle 120 as well as for the oscillatory movement of the shaft 134.

To facilitate the removal and replacement of the stem in the chuck 12, the breakermechanism is provided with a fork 170 to engage the chuck ring 54 of the chuck 12 and force the same in against the action of the springs 56, in order to release the balls 52. The stem leads may then easily be slipped into and out of the chuck. The fork is rectilinearly movable toward and from the chuck and is integral with a slide 172, rectangular in crossk section, slidable in a slide box 174 of conforming cross section, the slide box being formed atY the top of a vertical bar 176 fastened at its lower end to 4a horizontal web of the bracket 64. At its rear end, the slide has Van ear 178 to which is pivoted =a pitman 180 connected by a bell crank 182 and thrust rod 184 to a rocker lever 186 carrying a cam follower roller 188 riding on the cam 190. All of the rocker levers` are held down to their respective cams by springs 192 tensioned between the rocker levers and the base of the machine. The pivot for the bell cranks 150 and 182 4is Ia stub shaft 194 mounted on a vertical plate 196 fixed on a fixed part 1-98 of'the machine and in journals 200 and 202 extendingV from the vertical web of bracket 64.

The timingV chart in FIG. 9 shows the precise timing cycle of parts. After the conveyor carrying the chucks has reached a rest position, the fork 170 is operated by cam to move in to press against the ring 54 of a chuck to allow easy withdrawal of a stem after which the wafer jaws 124 close on the wafer by operation of cam 164. After the jaws have closed on the wafer, the wafer jaws are withdrawn by action of cam 156 to place the dummy lead or leads 32 in the .path of. movement of theV break off finger or fingers 116. Then the nger 116 is oscillated by cam 106 to snap or Vflick offrthe unwanted part of the wire 32 after which itreturns to its normal position. The jaws 124 are again moved close to the chuck to reinsert the stem in the chuck, the wafer jaws are opened, vfthe fork retracted and the conveyor indexed to bring a new stem before the breaker apparatus. This completes the cycle.

What is claimed is:

l. A breaker for operating on stems provided with leads, including a dummy lead, extending through a wafer, said breaker comprising an indexible conveyor, equally spaced chucks mounted on said conveyor, each chuck having lead clamping means and a shiftable part to release the lead clamping means, release mechanism located at a fixed station along the conveyor for operating on the shiftable part to release the clamping means, a translatable carrier at said station to engage and withdraw a released stem from the chuck a distance sufficient to free the dummy lead from said chuck, and a finger at said station movable in a direction toward the dummy lead and in a plane transverse to the direction of translation of the carrier to engage a portion of the dummy lead and, by lateral thrust thereon, break it ofl? at the wafer.

2. A breaker for operating on stems provided with leads, including a dummy lead, extending through a wafer, said breaker comprising an indexible conveyor, equally spaced chucks mounted on said conveyor, each chuck having lead clamping means and a shiftable part to release the lead clamping means, release mechanism located at a fixed station along the conveyor for operating on the shiftable part to release the clamping means, a fixed mounting at said station, a translatable carrier axially slidable in said mounting to engage and withdraw a released stem from the chuck a distance sufficient to free the dummy lead from said chuck, a finger mechanism rotatable in said mounting to orbit said finger about an axis, and means on the mounting to move the linger in a direction toward the axis as it orbits to cause the finger mechanism to engage a portion of the dummy lead and, by lateral thrust thereon, break it olf at the wafer.

3. A breaker for operating on stems provided with leads, including a dummy lead, extending through a wafer, said breaker comprising an indexible conveyor, equally spaced chucks mounted on said conveyor, each chuck having lead clamping means and a shiftable part to release the lead clamping means, release mechanism located at a fixed station along the conveyor for operating on the shiftable part to release the clamping means, a fixed mounting at said station, a translatable carrier axially movable in said mounting to engage and withdraw a released stem from the chuck a distance sufficient to free the dummy lead from said chuck, and a biasedly mounted finger mechanism carried by said mounting, means on the mounting to move the finger mechanism in a direction toward the dummy lead, means to move the finger mechanism in a plane transverse to the axis of the carrier, all whereby the finger mechanism may engage a portion of the dummy lead and, by lateral thrust thereon, break it off at the wafer, said two means comprising a cam ring xedly mounted on the mounting perpendicular to the axis of the carrier and having an undulatory surface on the inner wall of the ring, said surface engaging the finger mechanism intermediate its ends and a spider rotatable Within the mounting pivotally supporting the finger mechanism and oscillatable about the axis of shift of the carrier.

4. A breaker for operating on stems provided with leads, including a dummy lead, extending through a wafer, said breaker comprising an indexible conveyor, equally spaced chucks mounted on said conveyor, each chuck having lead clamping means and a shiftable part to release the lead clamping means, release mechanism located at a fixed station along the conveyor for operating on the shiftable part to release the clamping means, a translatable carrier axially movable at said station and having jaws to engage a wafer of a stem and withdraw a released stem from the chuck a distance sufficient to free the dummy lead from said chuck, and a finger at said station movable in a direction toward the dummy lead and in a plane transverse to the axis of shift of the carrier to engage a portion of the dummy lead and, by lateral thrust thereon, break it olf at the wafer, said jaws being pivotally mounted on the carrier, and means for spreading the jaws preparatory to their engaging a wafer, said last means comprising a rod oscillatable about the axis of shift of the carrier and having rollers to engage inner faces of the jaws and spread them apart as the rod is oscillated.

5. A breaker for operating on stems provided with leads, including a dummy lead, extending through a wafer, said breaker comprising a conveyor, drive means for indexing the conveyor, equally spaced chucks mounted on said conveyor, each chuck having lead clamping means and a shiftable part to release the lead clamping means, release mechanism driven by the drive means located at a fixed station along the conveyor for operating on the shiftable part to release the clamping means, a translatable carrier driven by said drive means at said station to engage and withdraw a released stem from the chuck a distance sufficient to free the dummy lead from said chuck and to subsequently reinsert the stem in the chuck, and a finger driven by said drive means at said station movable in a direction toward the dummy lead and in a plane transverse to the direction of translation of the carriage to engage a portion of the dummy lead and, by lateral thrust thereon, break it off at the wafer.

6. A breaker for operating on stems provided with leads, including a dummy lead, extending through a wafer, said breaker comprising an indexible conveyor, a motor driven shaft driving said indexible conveyor, equally spaced `chucks mounted on said conveyor, each chuck having lead clamping means and a shiftable part to release the lead clamtping means, a countershaft movable with said motor driven shaft, release mechanism located at a fixed station along the conveyor, cam means on the countenshaft for operating on the shiftable part to release the clamping means, a fixed mounting at said station, a translatable carrier axially movable in said mounting to engage and withdraw a released stem from the chuck a distance sufficient to free the dummy lead from said chuck, cam means on the counters'haft to operate the carrier, a finger mechanism at said station movable in a direction toward the dummy lead and in a plane transverse to the axial movement of the carrier to engage a portion of the dummy lead, and by lateral thrust thereon, break it off at the Wafer, cam means on the mounting cooperative With the finger mechanism to control the motion of lthe finger mechanism toward and from the axis of movement of the carrier and cam means on the countershaft to move the finger mechanism orbitally about the said axis.

7. In a Wire breaker, a vertical fixed support, a cam ring mounted on the front face of the support, said ring having an inner scalloped wall, a horizontal bearing in said support, a sleeve insaid bearing provided with a spider at its forward end in advance of the cam ring, at least one lever pivotally mounted by said spider, said lever having a finger directed toward the axis of the bearing at its forward end and a cam follower opposite the scalloped Wall lof the ring at its rear end, a spring biasing the cam follower against the ring, mechanism to oscillate the sleeve, a hollow axle within the sleeve, jaws biased toward each other carried at tlre forward end of said axle, mechanism to reciprocate the axle within the sleeve, a shaft carried by and shiftable with the axle, mechanism to `oscillate the shaft, a jaw opening mechanism carried at the forward end of the shaft, a chuck for carrying a stem, provided with leads, positionable before the jaws, and means for operating all the stated mechanisms in timed relation to cause the jaws to grasp a stem Within the chuck, Withdraw the same from the chuck, to oscillate the spider to cause a nger to flick off a lead from the stem, to cause the jaws to reinsert the stem in the chuck and to again open the jaws.

the addition of a xed key` on the axle riding` in `a. xed

keyway on the support to prevent the axle from rotating inthe sleeve.

References Cited in the le of this patent UNITED STATES PATENTS Ames May 1, 1956 annu.. v;-

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