US2361517A

US2361517A - Sealing apparatus

Info

Publication number: US2361517A
Application number: US296064A
Authority: US
Inventors: Arthur J White; Anthony J Marshaus
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1939-09-22
Filing date: 1939-09-22
Publication date: 1944-10-31
Anticipated expiration: 1961-10-31
Also published as: FR867138A; GB542399A

Description

Oct 1944. A. J. WHITE ETAL SEALING APPARATUS 2 Sheds-Sheet 1 S, ,w w e n .tmwwv S h P O w w i tJ aA n P Guns Q E Im kT 9 At M a w m m Oct. 31, 1944. A" WHITE 2,361,517

SEALING APPARATUS Filed Sept. 22, 1939 2 Sheets-Sheet 2 I l I I I l I I I I l I I I I I I I l I I I l I I I I l I I Inventors Ar-Lhuf- J. White. Anthony .J. Marshaus,

by 4, 84 I Their" Attorhey.

Patented Oct. 31, 1944 SEALING APPARATUS Arthur J. White, Cleveland Heights, and Anthony J. Marshaus, East Cleveland, Ohio, assignors to General Electric Company, a corporation of New York Application September 22, 1939. Serial No. 296,084

8 Claims.

Our invention relates to apparatus for sealing vitreous bodies together and more particularly to apparatus for sealing the stems of incandescent and are lamps and other electrical devices to the enclosing bulb or envelope.

According to the method disclosed in application Serial No. 176,910, A. J. White, filed November 27, 1937, two vitreous bodies such as a stem and an envelope for an enclosed arc lamp can be sealed together by the heat generated by induction in a conductive body located adjacent and preferably in contact with one of the vitreous bodies. The principal object of our invention is to provide apparatus for sealing two vitreous bodies together in this manner.

Another object of our invention is to provide apparatus for automatically positioning the vitreous bodies in sealing relation and manipulating and timing automatically all operations in the sealing process.

Another object of our invention is to provide,

apparatus for sealing the electrode supporting stems in both ends of the vitreous tube forming the enclosure or envelope for an arc lamp.

Other objects and advantages of our invention will be apparent from the following detailed description of a species thereof and from the accompanying drawings.

In the drawings, Fig. 1 is a plan view of a sealing apparatus comprising our invention with some of the heads thereof only outlined and others broken away to show the underlying parts; Fig. 2 is a vertical section through the turret along line 2-2 of Fig. 1 with the adjacent head shown in elevation; Fig. 3 is a perspective view of the cage for supporting the stem and the end of the vitreous envelope to be sealed thereto; Fig.

4 is a front elevation of the gripping jaws of the head; and Fig. 5 is a diagrammatic perspective view of the operating and repositioning means for the push down apparatus and induction coils respectively.

The sealing apparatus shown in Fig. 1 is comprised of sixteen heads I0 mounted about the periphery of the turret H which is indexed in a counter-clockwise direction in a manner to advance each 01. the heads it] into each of the stations indicated in turn. An operator stands before stations A and B and, in the interval the heads III are at these stations, inserts a stem in cage l2 (Figs. 1 and 2) and the tubular vitreous envelope l3 in between the jaws l4 and I5. As shown in Fig. 3, the stem It comprises a flared stem tube l'l sealed to one end of the exhaust tube and and the operation of inserting said stem I 6 in the machine consists in threading the lower ends of the exhaust tube l8 and the leading-in wires l9 and 20 through the center opening in the 'holder 2| and resting the flange 22 of the stem tube H on the ring-'shaped heating element 23 carried thereby. .An upwardly projecting button 24 on the holder 2| serves to locate the stem ii and to provide protection for the leading-in wires l9 and 20 at this point. The holder 2| is made of a non-magnetic and non-conductive material such as asbestos or sillimanite whereas the heating element 23, which rests in a similarly shaped circular groove therein, is made of a conductive material which does not stick to the vitreous stem l6, such as carbon. The heating element 23 fits loosely in the holder 2| and can be lifted out and replaced as often as desired. As there is some danger of the exhaust tube 13 being struck and broken off during the operation of the sealing apparatus. the lower end thereof enters a central aperture in the non-conductive guard 25 which i3 and about portions of the leading-in wires I9 '65 is mounted on continuations of the metal side rods 26 on which the holder 2i is mounted. The side rods 26 and the plate 21 from which they extend are, in this instance, of brass. The metal bracket 28 attached to the turret ll by the nut 23 supports the cage assembly l2.

The insertion of the tubular envelope or bulb l3 takes place after the operator opens or separates the jaws l4 and i5 by swinging the lever 33 to one side. The Jaws l4 and i5 are pivoted on separate rods 31 extending downward from bracket 32 and are normally held in a closed position by the wedge 33 which takes a position between the rollers 34 on rearwardly extending portions thereof. When said laws It and I5 are opened, the wedge 33 is withdrawn from between said rollers 34 by the lever 35 which is connected to the manually actuated lever 30 through the link 36 and a spring 31 extending between posts in the rearwardly extending portions of said jaws It and I5 separates said jaws. The lever 35 engages the wedge 33 through a pin 38 entering a slot in the lever 35 and causes the Jaws l4 and i5 to close when manual pressure is taken from the lever 30 as the contracting force of the spring 39 then pulls it out of position. The spring 33 extends between posts in the lever 35 and the bracket 32 which also provides guide ways on top of the laws It and i5 for the wedge 33. Jaw it engages the tubublar envelope or bulb i3 at two difierent points through the V-notched plates 40 whereas Jaw i5 engages said envelope or bulb i3 through the rubber insert 4| which prevents it from being moved longitudinally while gripped thereby.

When the envelope I3 is inserted in the jaws l4 and I5, the rim of the opening in the lower end is rested on the flange 22 of the stem |6 as shown in Fig. 3 and said jaws are at a height determined by the position of the rods 3| which support the collars 42 on which the said jaws rest. The rods 3| are mounted in vertical openings in the stationary bracket 43 fastened to the standard 44 extending upward from the bracket 28 and are positioned vertically by the yoke 45 on the lower ends thereof. At this time, the pressure of expansion of the spring 46 within the upper end of the standard 44 turns the lever 4'! which engages the pin 48 held by the yoke 45 so that said yoke 45 is kept against the bracket 43. The lever 41 pivots on the pin 49 held by bracket 43 and is permitted to swing to this position only as the pawl 50 is tripped between unloading and reloading of the envelope or bulb l3. The tripping is done by the screw on the end of the bar which extends downward between the jaws l4 and I5 from the wedge 33 and backward through an opening in the standard 44 and which is moved back against the pawl 50 by the greater closing movement of jaws N and I5 when the envelope or bulb I3 is not therebetween.

The next succeeding stations taken by the head H] are idle ones and it is not until stations E and F are reached that electrical energy is introduced in the ring-shaped heating elements 23 carried by the cages l2. At these stations, two

hollow coils

52 and 52 connected to a source of high frequency electricity are moved up about the cages I2 so as to induce a relatively high current in the heating elements, sufficient to cause the outer portion of the flange 22 of the stem |8 and the lower portion of the rim of the bulb l3 to be fused and sealed together. In some instances, the outer portion of the flange 22 is melted down at station E and it becomes desirable for the bulb |3 to be pushed down thereagainst again at this station; otherwise the bulb l3'is not moved down until station F is reached. Whether the bulb I3 is moved vertically depends on the adjustment of the bulb shifting means which consists of the cross arm 53 mounted on the upper end of a vertical rod 54 passing through the center of the machine and means held thereby which engages and raises the inner end of the levers 41 of the heads ID. The end of the arm 53 adjacent the heads ID at stations E and F carries an angular bracket 55 on which is mounted the guides 56 for the push pins 51 and an upward movement of the arm 53 carries said pins 51 against the screws 58 in the end of the levers 41. The push pins 51 rest on springs 59 within the guides 56 which limit the pressure with which the bulbs l3 are pressed down onto the flares IS. The compression force under which the spring 53 is held is established by the distance the adjusting screw 60 is screwed in or out of the guide 55. If no vertical adjustment of the bulb I3 is desired at station E, the screw 60 or guide 55 can be lowered so that the push pin 51 does not engage the screw 58. Once the lever 41 and bulb H! are moved, there is no further use for the shifting means as the pawl 50 which is pivotally mounted on said lever 41 at 6| is pressed against the teeth of the insert 62 by the spring 53 and is held in place thereby.

The cross arm 53 of the shifting means is moved vertically in proper time relation to the other operations of the machine in the same manner as the induction coils 52' and 52 by cam means on the single drive shaft 64 shown in Fig. 5. The drive shaft 54 is mounted below the turret II in the frame (not shown) of the machine and is the means for actuating the indexing means (also not shown) for the turret The rod 54 on which the cross arm 53 is mounted extends downward through the hollow column 65 supporting the turret II and connecting it to the indexing means and is actuated from the cam 66 through the lever system comprising levers 51 and 68. Lever 61 is pivotally mounted on the frame of the machine through the bracket 63 and engages the ways of the cam 66 through a roller (not shown)' whereas lever 63 is pivotally mounted on the bracket 10 extending from the frame and is connected to the lever 61 through links II and to rod 54 through link 12 and block 13. The actuatin means for the induction coils 52' and 52 at these stations comprises the cam '14; the lever 15 which engages the said cam 14 through a roller (not shown) and the vertically disposed rod '16 which is attached to said lever 15 through the link I1 and block 18 and which extends upward through the frame and the bracket '19 thereon to the platform 80. Lever 15 turns about the pivot provided in the bracket 8| which is fastened to the frame. Both

induction coils

52 and 52 are connected in series by the single piece of flattened pipe forming both coils and are attached to the platform Bllby the end portions thereof which are clamped onto the insulating plate 82 thereon.

During the intervals the head I0 is at stations E and F, the heating element 23 is increasing in temperature and during the movement of the head I0 through stations G and H some effective heat still remains therein. It is, therefore, preferred that the bulb l3 and stem I6, now as a single unit, be left in the head l0 unitl station J is reached. The lamps taken from the machine are first placed in an annealer which heats the sealed end and are then transferred to a rack to cool.

The function of one half of the stations of the machine has now been described and the sealing of a stem l6 over one end of the tubular envelope or bulb I3 is complete. The other half of the machine duplicates the operations performed by the first half in sealing a second stem to the opposite end of the bulb l3. To do this, the bulbs II are removed from the heads I0, turned end for end, and returned thereto. A considerable saving in equipment and handling is realized by this method of operation since some of the apparatus required for the first half also functions in the second half and since handling of the bulbs I3 is reduced to a minimum. The bulbs l3 and stems in this instance are inserted in the head I. while they are at stations J and K in the same manner as these operations were performed at stations A and B; the stem first being placed on th heating element 23, thereupon the bulb I3 is reinserted in the jaws |4-|5 and pushed down into enzazement with the stem. As described heretofore in connection with the sealing of the first stem, the leads I9 and 20 are threaded through the central opening in the holder 2| and the stem is positioned laterally by the button 24. Between the time the bulb I3 is removed from the head II and returned thereto, the operator removes his hand from the release lever Ill of the jaws l4|5 so that they close and the screw on the end of bar 5| engages the pawl 50 which is withdrawn from between the teeth of the insert CI. The laws ll-I5 are then free to rise to their upper position and take a position corresponding to that held at stations A and B. Following the insertion of the stem and bulb I3 into the head ll, it is indexed in turn to station L and then to station M which are idle stations.

The heat for sealing is created in the heating elements 23 by the electrical current induced therein by

theinduction coils

84 and 85 at stations N and O. The induction coils 84 and 85 are mounted on insulating plate 88 on a movable platform 81 like in the prior instance but are moved in and out of operative relation to the cage H of the head I by movement of the rod 88 (F18. 5) which is actuated from lever 89 through link 90 and block 8|. Lever 89 pivots on a pin extending from the bracket 92 on the frame and engages the ways of the cam 93 through a roller not shown. For reasons of simplicity, the induction coils 84 and 85 are connected in series with the other induction coils 52' and 52 at stations E and F. The series connection is made through hollow flexible pipe 84 and the connections from the source of high frequency current 98 are made through tubular pipe 95 to one end of coil 84 and lead 98 (Fig. 2) to the end 83 of coil 52. The cooling water is introduced into the hollow interior of the pipe 95 through the rubber hose 8'! and after flowing through each of the

coils

84, 85, 52' and 52 passes out the coil end 83 (see Fig. 2). The bulb IS in this instance is pushed down by means on the other end of the cross arm 58 in the same manner as at stations E and F. The period taken by the head ill in passing through the next two stations P and Q permits the lamp seal to cool. The finished lamp is removed .from the machine at station A. 1

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

1. Apparatus for sealing a pluraiityof vitreous bodies together comprising a heating element of material which is capable of being heated by induction and to which the fused vitreous bodies will not permanently adhere, said element being arranged to engage and support at least one of the vitreous bodies at the area where it is to be sealed, a holder of non-magnetic material for supporting the heating element, a supporting cage for the holder comprising rods for suspending said holder, means independent of said cage for holding a second vitreous body in sealing relation to the first-mentioned vitreous body, and an induction coil disposed in axial alignment with said cage and means for moving said coil to a position surrounding the said cage and the holder for inducing electrical currents into said heating element to heat it to a high degree so that heat is conducted therefrom to the vitreous bodies in sufficient quantity to cause the adjacent portions thereof to be fused together.

2. Apparatus for sealing a plurality of vitreous bodies together comprising a heating element of material which is capable of being heated by induction and to which the fused vitreous bodies will not permanently adhere, 'said element being arranged to. engage and support at least one of the vitreous bodies at the area where it is to be sealed, a holder of non-magnetic material for supporting the heating element and positioning the said vitreous body thereon, a supporting cage for the holder comprising rods for suspending said holder, gripping means independent of said cage for holding a second vitreous body, an induction coil disposed in axial alignment with said cage and means for moving said coil to a posi.

tion surrounding said cage and holder for induc- 18 electrical currents into the heating element to heat it to a high degree so that heat is conducted therefrom to the vitreous bodies in sufficient quantity to cause-the adjacent portions thereof to be fused together, and means for moving said gripping means nearer the heating element for pressing the second-mentioned body against the first to compress the seal therebetween.

3. Apparatus for sealing electric lamp stems in both ends of a tubular envelope comprising an intermittently rotatable turret, a plurality of heads mounted on said turret and carried thereby through a plurality of stations, each of said heads comprising a stem support member capable of being heated by induction and arranged to hold a stem in an upright position, each of said heads further comprising an envelope holder arranged above and in alignment with said stem support member to hold an envelope in a vertical position with its lower end enclosing and engaging said stem, induction coils located at at least two heating stations in vertical alignment with the path of movement of said heads, means for mov ing said coils vertically in timed relation'to the turret movement to and from positions surrounding stem support members temporarily located at said heating stations to heat said stem support members by induction and thereby fuse the stems thereon to the adjacent ends of the envelopes, said coils being separated by at least one station to permit reversal of the envelope thereat andinsertion of a second stem in the head at said one station so that the said second stem is fused to the other end of the envelope at the second heating station.

4. Apparatus for sealing a stem to the end of an electric lamp envelope comprising a horizontal turret rotatably mounted on a vertical hollow column, a plurality of heads carried by said turret through a plurality of stations, each of said heads comprising support means mounted on saidturret, a stem holder rigidly supported by said support means, and an envelope holder in vertical alignment with said stem holder and slidably mounted on said support means for vertical movement, means located at stations on opposite sides of said turret for effecting heating and sealing of a stem and adjacent envelope end in heads located at said opposed stations, and means for vertically moving the envelope holders of the opposite heads located at said opposed stations tov ward the co-operating stem holders to compress the seals between the stems and envelopes in said heads, said last-mentioned means comprising a horizontal cross arm extending diametrically across and above said turret between said opposite heads, the envelope holders on said heads being provided with engagement means engageable by the ends of said cross arm, a vertical shaft extending through the hollow column and carrying the said cross arm at its upper end, and means for reciprocating said shaft vertically to carry the cross arm to and from engagement with the engagement means of envelope holders on said opposite heads to actuate said holders.

5. In apparatus for sealing a stem to the end of an electric lamp envelope, a headcomprising support means, a stem holder rigidly'supported by said support means, and an envelope holder comprising separable Jaws in vertical alignment with said stem holder and mounted to slide bodily on said support means in a vertical direction, 9, laterally extending lever connected at one end to a portionof said envelope holder and mounted on a pin extending from said support means to pivot in a vertical plane, spring means normally tending to pivot said lever in a direction to hold said envelope holder in a raised position, means for fusing said stem and envelope together, actuating mechanism arranged to engage said lever and pivot it against the action of said spring means to lower the envelope holder and the envelope therein to compress the fused portions of the stem and envelope against the said stem holder, a ratchet carried by said support means adjacent to said lever, a spring-pressed pawl carried by said lever in a position to normally engage said ratchet and thereby retain the envelope holder in its lowered position against the action of said spring means on said lever, means for actuating said envelope holder jaws comprising a wedge member movable into and out of position between portions of said jaws, and release means comprising a bar member connected to said wedge member and terminating at a point adjacent to said pawl, said bar member being adapted to engage said pawl and release it from the ratchet upon movement of said wedge.

6. In apparatus of the class described comprising a horizontal turret rotatably mounted on a vertical hollow column, and a plurality of heads mounted on the periphery of said turret, each of said heads comprising support means and an envelope holder mounted for vertical movement on said support means, means for vertically moving envelope holders in heads located at diametrically opposed positions on said turret comprising a horizontal cross arm extending diametrically across and above said turret, said envelope holders being provided with engagement mean engageable by the adjacent ends of said cross arm, a vertical shaft extending through said hollow column and carrying said cross arm, and means for moving said shaft vertically to carry the ends of said cross arm into engagement with the holder-engagement means and thereby effect vertical movement of said holders.

7. In apparatus of the class described, comprising a horizontal turret rotatably mounted on a vertical hollow column, and a plurality of heads mounted on the periphery of said turret, each of said heads comprising support means and an envelope holder mounted for vertical movement on said support means, means for vertically moving an enevlope holder in a given head comprising a horizontal cros arm extending radially outward from the center of said turret to a position adjacent said head, said envelope holder being provided with engagement means engageable by the outer end of said cross arm, a vertical shaft extending through said hollow column and carrying said cross arm, and means for movingsaid shaft vertically to carry the outer end 01' said cross am into engagement with-the holder engagement means and thereby effect vertical movement of said holder.

8. In apparatus of the class described, comprising a horizontal turret rotatably 'mounted'on a vertical hollow column, and a head mounted at the periphery of said turret, said head comprising supportmeans, an envelope holder slidably mounted for vertical movement on said support means, means for moving said holder between two vertically spaced positions on said support means comprising a horizontal lever connected at one end to said holder and mounted on a portion of said support means for pivotal movement in a vertical plane and having a free end extending beyond the point where it is mounted on said support means, spring means urging said lever in a direction to maintain said holder in one of said two vertically spaced positions, and means for moving said holder to the other of said two positions comprising a horiozntal cross arm extending radially outward from the center of said turret to a position adjacent the free end 01' said lever, a vertical shaft extending through said hollow column and carrying said cross arm, and means for moving said shaft vertically to carry the outer end of said cross arm into engagement with the said free end of said lever and thereby eiTect vertical movement of said holder.

ARTHUR J. WHITE. ANTHONY J. MARSHAUS.