US1655050A - Sealing-in machine for tubes and bulbs - Google Patents

Description

Jan. 3, 1928.

c. EISLER SEALING-IN MACHINE FOR TUBES AND BULBS Filed April 25, 1925 2 Sheets-Sheet 1 ATTORNE Jan. 3, 1928.

C. EISLER SEALING-IN MACHINE FOR TUBES AND BULBS Filed April 25, 1925 2 Sheets-Sheet 2 I lllll IIIH 17 M05. L y 74v ATTORNEY Patented Jan. 3, 1928.

UNITED STATES PATENT OFFICE.

s nmin fled April :5, 1m. Serial Io, 25,747.

This invention.'relates-to a machine for.

sealing in the stems of radio tubes and the like and particularly to sealing in of the character set forth in my apphcatlon Serial No. 6,527, filed February 3, 1925. That application coversa novel method of forming stems of the general character set forth in J aeger Patent No. 729,182, May 26,

1903 and comprising generally a stem'tube with a flare for sealmg to the bulb or tube neck, and an exhaust tube havin its inner end bent laterally ,and fused to t e side of the stem tube at a point removed from the sealed end thereof. The machine of the present a plication is of more general application, owever as to certain of its features,

' and may be utilized, for example, for sealing tated and the sealing-in expedited. A still further object is a mechanism of the above indicated character including a novel single oint sup ort for the stem while being sealed mto the ulb or tube whereby strams and breakages are substantially reduced during the sealing-in and the removal of the sealedin bulb may be readily and quickly efiected for centering the mount, if necessary, b the operator before the setting of the p astic seal. A still further object is the automatic removal of the stem support, if desired, after the fusing takes place and before the setting without exerting pull on the plastic seal. My invention also contemplates a simplified revolving head structure whereby the parts may be economically produced and assembled and adjustments thereof facilitated for various sizes of lamps, and a simplified driving and control mechanism for effecting the intermittent and rotating movements.

For a better understanding of the above indicated novel features of the invention and others which will hereinafter appear, reference may be .had to the accompanying 'drawmgs forming a part of this specification, wherem:

Fig. 1 is a plan view of a sealing-in machme embodymg m invention, more or less dlagrammatlcallyi ustrated,

Fig. 2 is a sectional view of the machine along the lines 22 of Fig. 1,

F1g. 3 1s a s de view, partly in section, of a il'ivolving head or spindle and associated P l Fig. 4 is a sectional view of the upper part of dthe stem support and cooperating parts, an

- Fig. 5 is a sectional view of the lower part thereof.

Referring to the drawings where like numerals designate similar parts throughout, I have mdicate'dmy invention as embodied in a machine having a trough like stationary base or table 17, the latter being carried by sultable standards, a' rotatable spider or frame 10 which is mounted for intermittent rotation thereon and a plurality of rotatable heads 1 carried by the spider 10. In the particular embodiment herein illustrated there are six of these heads 1, although in practice as man of these heads may be provided as are esired. Intermittent movement of the spider 10 is efiected through the med um of Geneva wheel 16 on the shaft 13 which is keyed to the spider, the Geneva wheel being driven by a cooperating driver 14' on a vertical counter-shaft 12, mounted in suitable bearings carried by the table 17. A worm gear 11 1s mounted on the Geneva 'driver shaft 12 and driven by the worm 15 on the driving shaft 2.

The various heads succemively occupy the pos tions A, B, O, D, E, and F as the ider 10 1s intermittently rotated, A and B in the two front positions where the sealed tubes or bulbs are taken off and new tubes and stems are inserted, while at positions C, D, E the parts to be fused together are gradually heated and at the position'F the concentrated heat applied to complete the fusing and the sealing of the bulb and stem together. The heads 1 with the bulbs and stems carried thereby are rotated about their axes at the positions C, D,'E and F from the driving shaft 2 bymeans of are 3 keyed to "the respective splndles and t e rubber frictional drive wheels 4 which are carried by vertical counter shafts 7 rotatably mounted in the table 17 there being a rubber drive 4 passes an endless chain 5.

adjacent each of the heating positions G, D, E, F. The shafts 7 pro ect downwardly through the table 17 an carry on the under side a series of sprockets 6 around which shafts 7 also carries on its lower end a spiral gear 9 which. meshes with a cooperating spiral gear 8 on the drive shaft 2 for continuously rotatin the drivers 4. The tubes and stems, assem led on the heads 1 1n either position A or B, are intermittently carried.

and the latter in turn carry on their upperends the bulb or tube support 30. The support is capable of adjustment longitudinally of the supports 29 and may be fixed in any desired position by means of the set screws 31. Each base 27 includes a hollow shaft 27 which is journaled as indicated on the spider 10 and carries on its lower end the driving gear 3. Through the center of the base 27 and the hollow shaft 27' passes the stem support including a hollow sealing rod 19, and this rod carries w1th1n its upper end the stem adapter and support 32, 35. The stem adapter is of tubular formand closed at its lower end, and it consists of two parts, a lower part which is screwthreadedly attached at its upper end to the interior of the upper end of the seallng rod 19 and an upper part 32 which is separably mounted within the upper part 35, the upper part being thereby removable without removing the whole support. Thetubular member 32-35 may be adjusted longitudinally of the sealing rod by means of the adjustable nut 36 which is screw-threadedly attached to the upper end of the part 35 and en es the upper end of the sealing rod 19. set screw 37 is provided for anchoring this nut in any adjusted posltlon. The part 35 of the stem adapter for the greater portion of its length below the externally threadedportion at the top is made of smaller diameter than the interior diameter of this sealing rod 19, but at its extreme lower end it has an exact fit with the bore of the sealing rod. Longitudinal grooves 20' are provided along the surface of the lower end of the part 35 and similar grooves 20 are cut through the external threadedportions of the upper end thereof for a purpose hereinafter set forth. In the particular embodiment herein, there are shown three such grooves equally spaced around both the upper and lower ends of the part 35 of the stem support. The stem adapter ma be provided at its upper end with a circu ar flange 41 One of these.

for engaginglthe flare of-the stem tube and sup rting t e stem in the desired position,

an the stem support is provided with a flaring opening at 1ts u per end to facilitate the insertion of the ste s with theirexhaust.

-tubes projecting downwardly and loosely therein and to permit ready removal-of the lamp bulbs or tubes after the sealing-in operation.

The sealing rod 19 is provided on its lower end with a circular shoe 34 and between the latter and the end of the hollow shaft 27 there is disposed a spring 23 which normally urges the sealing rod and the shoe 3.4 in a downward direction against the circular track 24 carried by the table 17 The track 24 preferably has a'bevelled 01f portion indicated at 24' in Fig. 3. This is for the purpose of causing an automatic lowering of the sealing rod 19 with the stem adapter 32 35 at posltions A and B to facilitate the ta ing off of the finished bulbs and lacing of new parts thereon. An adjustable sto 25 is carried by the base portion 27 whic coe erates with a collar 33 carried by the sea ing red at a point thereabove to limit the downward movement of the sealing rod. A key 26 in the base 27 cooperates -with a long keyway 28 in the sealing rod 19 to effect the rotation of the rod 19 with the base 27, but at the same time permitting the .longitudinal relative movement, if desired.

The beveled off portion 24' may beginimmediately after leaving the position F and in that case, the Weight of the filament stem may be suflicient to lower or tilt the filament stem and mount with reference to the bulb, due to the fused and plastic condition of the seal. However, the operator upon removal of the bulb may, if necessary, slightly adjust the stem with reference to the bulb to properly osition the mount therewithin, since usual y the seal is still slightly plastic when position A is reached. The operation of the iealing inmachine is substantially as folows:

the operator inserts within the stem adapter Upon the heads located at either A or It 32, 35 a stem with its exhaust tube 43 extending loosely down into the stem tube su port and with its flare 44 resting upon the ange support 41. She also inserts over this stem and within the tube support 30 a tube 45 with its neck or skirt 46 extending down beyond the flare 44. With the parts thus assembled at position B, at the next intermittent operation the head 1 is automatically moved to position G where the driver u 11 coming into driving relation with the rub r wheel 4 at that position is rotated while a flame from the single burner 40 is caused to play upon the bulb or tube neck'in the vicinity of the flare 44. At the next intertion D where two or more flames are-caused number of flames neck and at positio concentrated flames are brought to bear upon the neck in the.

vicinity of the flare 44 which causes the fusing or welding of the flare 44 of the stem to the neck with considerable attenuation of the neck or skirt 46 down beyond the flare. At this position F a small continuously flowing blast of air from the nozzle 47 is directed up into the lower end of the hoHow sealing rod 19 which blast of air passes upwardly in the direction of the arrows in Figs. 4 and 5 through thegrooves and 20 and to the space above the ML justing nut 36, theair pressure being sufii: cient to blow off the surplus glass as it is melted from the lower portion of the neck Est below the flare 44. The tube may provided withra lateral opening 48 regis-' termg with a smaller opening 49 in the sealing rod 19 to keep the interior of the tube or bulb in communication with the atmosphere, as such communication is always essential in sealing stems into bulbs. The head stays at osition F long enough to effect the seal w ereupon the intermittent o eration takes place again and the head t en goes to position A where the finished tube is removed to provide for the positioning of another bulb and stem to be sealed in. After leavin position F the stem support is automatica ly lowered by the shoe 34 running down the cam surface 24'.

This automatically removes all support for and engagement with the stem, permitting the latter to yield freely during the cooling of the weld without hindrance from the support. Moreover, the lowering of the stem support at positions A and B facilitates I'claim and desire to the positioning of the lamp parts thereon.

The sur his neck 46 of the tube 45, if not broken be ore it reaches positions A and B is'broken ofi by the operator whereupon it falls into the trough like table 17 and from there it is carried by a brush or rake 22 to an opening 21 in the table for dumping into asuitable receptacle. Y

Having thus described my invention, what protect by. Letters Patent is: g y

1. In a head for machines for sealing mounts in tubes or bulbs. a hollow rod having an opening through its wall, and a stem adapter secured near its upper end therein with a portion of the adapter extending above the rod and terminating in a seat for engaging the flare of the mount to be sealed in, the stem adapter being hollow to .loosely receive the exhaust tube of the mount, the lower end of. the adapter being of a diameter to fit the bore of the rod and protenor well open at the top and mounts in tubes adapter which is externally l I vided with an external longitudinal slot constitutin a passage for air to blow of! the fused gIass and a so provided with an open ing through its wall adapted to register with thia1 opening through the wall of said hollow ro 2. In a head for machines for sealing mounts in tubes or bulbs, a stem ada ter provided with a seat at one end adapts to engage the .flare of the mount with an inclosed at its bottom to receive the exhaust tube of the mount and with thickened walls at its lower end formed with one or more external longitudinal slots, and with an opening throu h the unslotted portion of the'thickened wa and a-hollow tube surrounding the adapter, fitting tightly the thickened walls thereof and provided with a wall opening registering with that in tl1e wall of the ada ter.

3. In a head for machines or sealing or bulbs, a stem ada ter provided with a engage theflare, of the mount, with an interior well open at the top and closed at its bottom to receive the exhaust tube of the mount and with thickened walls at its lower end formed with one or more longitudinal slots, and with an openin through the unslotted portion of the thic ened wall, and a hollow tube surroundin the adapter, fitting tightly the thickened walls thereof and provided with a wall opening registering with that in the wall of the adapter, the adapter and tube having exterior and interior screw-threads securing them together.

4. In a head for machines for sealing mounts in tubes or bulbs, a stem adapter formed with a seat for the mount and a well to receive the exhaust tube of the mount, the

adapter being closed at the bottom, an outer tube secured about the adapter, said tube and adapter being formed to provide passages for passage of air around the tube to points below the seat of the adapter and with a separate air pamage from within the well through the walls of the adapter and tube.

5. In a sealing in machine a revolving head including a bulb support and a stem support adapted to support a stem in sealing relation with the bulb, said stem support including a hollow sealing rod, a stem threaded near its upper end to engage with the internally threaded upper end of the sealing rod and an adjustable nut disposed about the threaded portion of the adapter for adjusting the adapter to difierent positions within the seal ngrod.

6. In a sealin in machine for lamp bulbs or tubes, a revo ving head including a bulb support, a stem support, said stem support be1ng adapted to engage the stem only by the restin of the stem upon the upper end of the stem support, means for intermittently seat at one end adapte to moving said revolving head from one po'sition to another and means for automatically removing the stem support from engagement with the stem without exerting "any pull thereu on immediately after the seal 15 efiected an before the plastic weld becomes set. I

7. In asealing-in machine forlamp bulbs or tubes a trough like table, a revpluble frame thereon carrying a multiplicity of revoluhle heads for sealing ,in lam bulbs and fusing' ofi the surplus necks of tlfehulbs d the scaling in operation, and a brush carri by the revoluble frame and engaging the interior-of the trough like table to con- 1l ve the surplus glass to an opemng provi ed in the table.

In testimony whereof, I haveiaigned my name to this specification.

CHARLES EISLER.

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