US2794699A - Manufacture of small lamps - Google Patents

Description

June 4,1957 EBER I 2,794,699

MANUFACTURE OF SMALL LAEQZS Filed Dec. 15, 1952 a Sheets-Sheet 1 June 4, 1957 M. EBER MANUFACTURE OF sum. LAMPS 3 She ets-Sheet 2 Filed Dec. 13, 1952 v INVENTOR ATTORNEY A June 4, 1957 M. EBER MANUFACTURE OF SMALL LAMPS I 3 Sheets-Sheet 3 TIFF/N6 OFF Call 57' DISC/709265 5 M Wm H Wm Wm M E a 6 W.

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United States Patent house Electric Corporation, East Pittsburgh, Pa, a corporation of Pennsylvania Application December 13, 1952, Seriai No. 325,826

'4 Claims. (Cl. 316-49) This invention relates to the manufacture of small lamps, such as incandescent filament lamps and photoflash lamps.

The principal object of my invention, generally C011? sidered, is the simplification of the manufacturing .procedure for small lamps, with a more complete mechanization.

Another-object of my invention is the provision of a lamp of the character specified, in which the bulb has a straight 'wall neck, the extreme end of which is pressed about leads, either those of the dumet type so as to connect with a conventional screw-threaded base, or multiple piece leads for pin contact construction.

A further object of my invention is the manufacture.

of small electrical devices involving the following steps:

1. Loading the leads into a holder;

2. Slipping a glass bead over the leads and fusing the same thereto, which step, however, is optional;

'3. The mounting of a filament, or other translation means, on the inner ends of said leads, and the coating with a primer, if a photoflash lamp;

4. Dropping the bulb over the mount so constructed, with the lower end of the neck fitting in a compression rubber;

5. Exhausting said bulb through said neck;

6. Filling the bulb with oxygen, if a photofiash lamp;

7. Pinching off the neck of the bulb to form a press-- type seal, and snapping olf the cullet below said seal; and

8. Fire polishing the rough edge of the seal.

Other objects and advantages of the invention will become apparent as the description proceeds.

In the drawing:

Fig. 1 is a side elevational view of a small lamp, of the photoflash type, embodying my invention.

Fig. 2 is an elevational view of the Imp of Fig. 1, looking from the left thereof.

Fig. 3 is a fragmentary vertical and axial sectional view of an exhaust machine (position No. l or position No. 2 in the view of Fig. 15), which may be used for manufacturing lamps in accordance with my invention.

Fig. 4 is a fragmentary plan of part of the machine of Fig. 3 (position No. 3 for the dotted line part, and position No. 4)', for the remainder, in the view of Fig. 15.

Fig. 5 is a fragmentary vertical and axial sectional view, on the line V-V of Fig. 4, in the direction of the arrows, but showing the parts in a subsequent position (No. 4 in Fig. 15 where the lead-in wires have been shaped and a glass bead placed around them.

Fig. 6 is a view corresponding to Fig. 5, but showing a subsequent position (No. 5 in Fig. 15) in which the glass bead'around the 'lead wires is being heated for fusing it into position with respect thereto.

Fig. 7 is a View corresponding to Fig. 6, but showing a subsequent position (No. 6 in Fig. 15 in which a bridgewire or ignitor filament has been mounted on the upper ends of said leads.

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Fig. 8 is a view corresponding to Fig. 7, but showing a subsequent position (No. 7 in Fig. 15) in which the ignitor material or combustion mixture has been secured to the upper ends of said leads.

Fig'. 9 is a view corresponding to Fig. 8, but showing a subsequent position (No. 8 in Fig. 15) in which the lead supporting jaws have been removed and the leads and combustion mixture are being cooled by a jet of air.

Fig. 10 is a fragmentary view of the apparatus shown in Fig. 3 in a subsequent position (-No. 9 in Fig. 15) in which an envelope or bulb has been placed over the supported mount of the device and the neck thereof is being heated.

Fig. 11 is a fragmentary sectional view, at right angles to the view of Fig. 10, and showing a subsequent position (No. 21 in Fig. 15) in which the heat-softened neck of a bulb has been formed into a press about the supported leads.

Fig. 12 is a horizontal sectional view on the line XIIXII of Fig. 11, in the direction of the arrows.

Fig. 13 is a view corresponding to Fig. 12 but showing the lamp in a subsequent position (No. 22 in Fig. 15 where it has been raised to a position where the cullet or neck portion beneath the press may be broken off.

Fig. 14 is a view corresponding to Fig. 13, but showing a subsequent position (No. 23 in Fig. 15) in which fires are used to polish the lower edge of the press.

Fig. 15 is a diagrammatic plan of an exhaust machine which may be used for practicing my invention.

Referring to the drawing in detail, there is shown in Figures 1 and 2, an electrical device or lamp 20 of the photoflash type, which has been manufactured in accordance with my invention. This lamp comprises an envelope or bulb 21, which is distinguished from those of the conventional type in that it has no tip or exhaust tubulation through Which the air was exhausted during the process of manufacture. Instead, it has a press .22 in the neck through which air was exhausted, and through which pass lead wires 23 and 24.

Although, in the present embodiment, the outer ends of the lead wires have rigid contact posts 25 and 26 projecting therefrom forming a base of the pin-contact construction yet, in the alternative, said leads may be of the customary dumet construction and each lamp may be completed by having a screw-threaded or other metal base secured to the press 22, as by basing cement or the like, one of said leads being connected to the shell of said base and the other to the central contact member, in accordance with conventional practice. The lamp of the present embodiment has the translation device 27 carried on the inner ends of the leads, said leads being shown as braced to one another by means of a glass bead 28 fused thereto.

The present embodiment of the translation device 27 comprises a bridge wire or ignitor filament 29 extending from one lead to the other, and the portions of said leads adjacent the upper ends thereof are coated with ignitor or combustible material 31. The bulb 21 may additionally enclose combustible wire or foil 32, conventional in character.

In manufacturing lamps in accordance with my invention, the leads 23 and 24 are first loaded, preferably auto matically, into upwardly opening pockets 30 in the inner member 33 of a bulb holder 34, at position No. l or No. 2 of Fig. 15. This may be one of the members or heads of an exhaust machine of the rotary type, such as shown diagrammatically in Fig. 15, and corresponding generally with that disclosed in the Mullan Patent No. 2,254,905, dated Sept. 2, 1941, and owned by the assignee of the present application. A similar exhaust valve for" such a machineis also disclosed in the Mullan Patent No. 2,113,798, dated April 12, 1938.

'Exhaust machines, such as indicated in Fig. 15, are

- usually provided with two pumps, a preliminary exhaust pump and a final exhaust. pump. The devices 2010 be evacuated, are first connected to a preliminary'e'xhaust pump and exhausted, as they travel with theconveyor, while mounted on heads 34, that is, they are moved from station to station while being exhausted. The same procedure is followed when the devices are subjected to the second or final exhaust pump.

Each conduit from the vacuum pumps to the devices being evacuated, is provided with a plurality of ports arranged to communicate with a plurality of slots, as described in the patents before referred to. The conveyor moves with the upper rotary disc valve section and communicates with the pumps through ports in said upper valve section, which successively communicate first with slots in the lower valve section connected to the preliminary pump, and then those which connect with the final pump, so that a progressive evacuation of the lamp bulbs or other devices is effected, during movement of said devices from the initial position where the bulbs are loaded on the machine, to a station where they are removed therefrom.

In view of the fact that the gradual exhaust of lamp bulbs or the like, as well as the admission and flushing of fill gas, is known to those skilled in the art, and machines for which the present invention is especially adapted have been described in the Mullan patents, before referred to, I will not further describe the exhaust operation; simply stating that my invention involves a modification on the machines of the patents mentioned, especially when such machines are equipped with the type of head illustrated in Fig. 3.

' The inner member 33 of each head 34, as shown in Fig. 3, includes an exhaust port 35'. By virtue of the construction previously disclosed, the valve sections which constitute a valve unit, serve to open and close the vacuum lines to the ports 35, as well as the lines to the oxygen supply pipes 36 if photoflash lamps are being manufactured. In' making such photofiash lamps, each may be first exhausted, then filled with oxygen, again exhausted, and finally filled with oxygen at the desired pressure.

Each head 34 is desirably provided with an apertured exhaust rubber or conduit 37 in the portion provided with the exhaust port 35. This exhaust rubber is mounted in a fitting 38, to which is threaded a cap 39 provided with a laterally-extending arm 41, and adapted to be camactuated to either press a washer member 42, tl rpugh ball bearings 43, against the exhaust rubber 37 to squeeze it about the lower end portion of the neck 44 of a bulb 21 at the proper time, to effect an air-tight connection therewith, or release the pressure thereon to facilitate insertion or withdrawal therefrom.

Air is exhausted from a bulb through the rubber tube connection 45, mounted in the head and adapted to be closed, as by means of a pinch-clamp 46 forming a valve which may be operated throughthe arm of said clamp, as desired or automatically upon the development of a leak. Connection with the vacuum pumps is efiected through the lower valve section andvacuum lines, by means of the rubber hose connection 45, a similar connection providing for the introduction of oxygen through pipe 36, as indicated by the reference character 93 in Fig. 3 of the Mullan Patent 2,254,905, a pinch clamp, as is there disclosed at 91, being employed for opening and closing such connection.

Operation Referring now particularly to Fig. 15, the'operation of the apparatus and conveyor diagrammatically illustrated in practicing my invention, may be as follows:

At station No. 1 or No. 2, a pair of lead wires are loaded onto the conveyor, by inserting the lower ends thereof into upwardly opening apertures in the inner member 33 of a head as it indexes at the station. These leads may be of a type, designated 23 and 24, with rigid contact portions 25 and 26, or they may be of the ordinary flexible dumet and serve for connection with a screw-threaded or other type of base. The leads above the contact portions 25 and 26 may be sufiiciently rigid so that they do not need to be connected together, or they may be fiexible so that the mount to be formed is rigidified by not only having the leads shaped, when the supporting head indexes at station No. 3, but encircled by a connecting bead upon indexing at station No. 4.

Thus, in accordance with one embodiment, the leads 23 and 24, after being indexed at station No. 3, are shaped as shown particularly in Figures 4 and 5, by shaping jaws 47, 48, 49 and 51, intermeshing as illustrated in Fig. 5. Each jaw is formed as indicated in dotted lines in Fig. 4, so that it carries the lead wires into notches 52 and 53, thereby spacing them in proper relation to one another, and shapes the leads between the upper set of jaws 47 and 48 and the lower set of jaws 49 and 51. The

leads 23 and 24 are thus desirably more closely spaced at their upper portions than at their lower portions, thereby adapting them for the reception of a connecting glass bead.

Such a bead 28 may then be applied over the shaped leads at station No. 4, resting on the shaping jaw 47. At station No. 5, as shown most clearly in Fig. 6, the bead is heated and fused around the upper portions of the leads, as by means of fires 55 and 56 from burners 57 and 53, respectively. I

At station No. 6, as shown most clearly in Fig. 7, an incandescent filament 29 may be mounted on the upper ends of the leads 23 and 24. However, if a photoflash lamp is being manufactured, such a filament is not made of the customary tungsten coil for continuously giving light, but is rather made of a wire serving to ignite a combustible mixture on the ends of the lead wires and usually also, by means of said mixture, a surrounding mass of combustible wire or foil filling the envelope.

At station No. 7, as shown most clearly in Fig'. 8, the combustible mixture or ignitor material 31 is desirably applied to the ends of the leads 23 and 24, as by suitable automatic means (not shown). That is, the jaws 47, 48, 49 and 51 may transfer the leads from their head, as indicated by the radial, outwardly-directed arrow in Fig. 15, dip the upper ends of said leads in a suitable combustible mixture, and return said leads to the head, as indicated by the radial inwardly-directed arrow in said figure. I

At station No. 8, the igniter material is preferably dried as by means of a blast of air issuing from a tube 63, as shown most clearly in Fig. 9.

At station No. 9, after the jaws 47, 48, 49 and 51 have opened to the dotted line position indicated in Fig. 4, a bulb 21 of the character illustrated in Fig. 10, is applied over the mount so formed, with 'the lower end portion of its neck 44 fitted in the apertured exhaust rubber 37, which is then in released position by virtue of the cap 39 being in its uppermost position with respect to the fitting 38.

i If an incandescent filament lamp is being manufactured, the bulb 21 is of course empty when applied. However, if a photofiash lamp is being manufactured, the bulb may be filled with combustible material, such as wire or shredded foil 32. After the bulb is loaded, it is indexed at station No. 10, where the cap 39 has been turned to squeeze the exhaust rubber 37 to make an airtight connection with the lower end 44 of the neck of the bulb 21. V p a The bulb is then indexed through station Nos. 11 to 17, inclusive, where it is exhausted and if the gas-filled type, also filled with suitable gas, or with oxygen if a photoflash lamp is being manufactured, through pipe 36. At station Nos. 18 to 21, inclusive, the lamp is subjected to the action of tipping-off fires, designated by the reference characters 64 and 65 in Fig. 10. At station No. 21, said fires having softened the neck sufficiently, the tipping-off operation takes place by jaws 66 and 67 swinging from open position, illustrated in dotted lines in Fig. 11, to closed position indicated in full lines in the same figure, about their supporting pivots 68 and 69, to squeeze the heated portion of the bulb neck 44 and form a flattened press 22.

The jaws 66 and 67 are desirably operated by suitable power-operated means, connected through links 71 and 72 and pivot pins 73 and 74, to arms 75 and 76 projecting outwardly from the jaws 66 and 67, respectively. Upon upward movement of said links, the jaws are separated, whereas upon downward movement thereof they are brought into compressive engagement into the neck of the bulb being tipped ofi. The neck-engaging portions of these jaws are desirably of special configuration, as shown most clearly in Figs. 11 and 12, so that they leave bulges 77 and 78 around the press 22 where the leads pass therethrough, thicken the lower edge of said press, and very much reduce the thickness of the section immediately below the thickened lower edge portion of the press 22, so that the cullet of waste portion 79 of the neck may be readily removed therefrom.

As the conveyor indexes from station No. 21 to station N0. 22, the tipped-off bulb 21 is raised from its head by conveyor suction device 89 and while also supported by steadying device 90 which is brought into contact therewith, the cullet 79 strikes a stop 81, adjustably positioned in a standard 82, as by means of a set screw 83, and is broken E and drops into a discharge trough 84, from whence it is removed from the machine (Fig. 13).

At station No. 23 the lower edge of the press 22 is smoothed or fire-polished by fires 85 and 86 from burners 87 and 88, respectively. At station No. 24 the bulb is removed from the machine, as by means of the conveyor suction device 89 by which it is supported. Said device 89 is connected to a suitable source or vacuum through pipe 91, whereby upon rising it withdraws the completed lamp from the head and thereby takes it away from the conveyor (Fig. 14).

From the foregoing, it will be seen that I have provided a method and apparatus for the production of a novel form of lamp, which lamp may be one of the vacuum or gas-filled incandescent filament type or one of the photoflash type. Novelty resides in the fact that it has neither a reentrant press and exhaust tube carrying portion, nor a tip through which exhaust is eifected. The bulb, on the contrary, is exhausted directly through its neck portion, generally conventional except that its lower edge portion is preferably slightly enlarged and cylindrical, so as to be directly gripped by the exhaust rubber of a head on an exhaust machine.

Although a preferred embodiment of my invention has been disclosed, it will be understood that modifications may be made within the spirit and scope of my invention.

I claim:

1. The method of manufacturing lamps having tipless envelopes with leads sealed therethrough comprising rigidly holding said leads in a predetermined spaced relation, mounting a filament on the free ends of said leads, placing a bulb with a preformed neck and opening over said leads, effecting an air-tight seal around the end portions of said neck, evacuating the bulb through its neck, heating said neck to plasticity, compressing the neck inwardly to form a press which hermetically encloses intermediate portions of said leads and seals ofi said bulb, releasing the end portions of the neck from said air-tight seal, and removing that portion of said neck which extends beyond said press.

6 2. The method of manufacturing lamps having tipless envelopes with multiple piece leads sealed therethrough for pin-type electrical connection comprising securing a rigid'contact-post base-pin to one end of each of said? leads, fixedly holding said leads by said base-pins in upright closely-spaced relation, shaping the free ends of said leads to a preselected configuration, threading a bead over said leads and fusing it to intermediate portions adjacent the upper ends thereof, mounting a filament on the upper ends of said leads, placing a bulb with a downwardly opening preformed neck over said leads, directly gripping the end portions of said neck to effect an airtight seal therearound, evacuating the bulb through its neck, heating said neck to plasticity, compressing the neck inwardly to form a press which hermetically encloses intermediate portions of said leads including the upper end portions of said base-pins and seals ofi said bulb, releasing the end portions of the neck from said air-tight seal, removing that portion of said neck which extends beyond said press, and fire-polishing the lower edge of said press.

3. The method of manufacturing photoflash lamps having tipless envelopes with leads sealed therethrough comprising rigidly holding said leads in a predetermined spaced relation, mounting an ignitor filament and combustion mixture on the inner ends of said leads, placing a bulb with a preformed neck and opening over said leads, efiecting an airtight seal around the end portions of said neck, evacuating the bulb through its neck, filling said bulb with oxygen, heating said neck to plasticity, compressing the neck inwardly to form a press which hermetically encloses intermediate portions of said leads and seals off said bulb, releasing the end portions of the neck from said air-tight seal, and removing that portion of said neck which extends beyond said press.

4. The method of manufacturing photoflash lamps having tipless envelopes with multiple piece leads sealed therethrough for pin-type electrical connection comprising securing a rigid contact-post base-pin to one end of each of said leads, fixedly holding said leads by said basepins in uprighbclosely-spaced relation, shaping the free ends of said leads to a preselected configuration, threading a head over said leads and fusing it to intermediate portions adjacent the upper ends thereof, mounting an ignitor filament and combustion mixture on the upper ends of said leads, placing a bulb enclosing combustible material and having a downwardly opening preformed neck over said leads, directly gripping the end portions of said neck to effect an air-tight seal therearound, evacuating the bulb through its neck, filling said bulb with oxygen, heating said neck to plasticity, compressing the neck inwardly to form a press which hermetically encloses intermediate portions of said leads including the upper end portions of said base-pins and seals ofi said bulb, releasing the end portions of the neck from said air-tight seal, removing that portion of said neck which extends beyond said press, and fire-polishing the lower edge of said press.

References Cited in the file of this patent UNITED STATES PATENTS 1,662,045 Patterson Mar. 6, 1928 1,736,766 Burrows Nov. 19, 1929 1,821,351 Loewe Sept. 1, 1931 2,109,274 Niclassen Feb. 22, 1938 2,133,492 Vatter Oct. 18, 1938 2,201,694 Illingworth May 21, 1940 2,204,204 Baier June 11, 1940 2,225,090 Wiener Dec. 17, 1940

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