Sept. 24, 19460 H. K. RlcHARbsoN 2,407,998 LAME‘ BASE Filed uai-ch 25, 1937 22 MM; W» ATTORNEY Patented Sept. 24, 1946 2,407,998 UNITED sTATEstPATENT OFFICE 2,407,998 IJAMP BASE Henry K. Richardson, Bloom?eld, N. l, assignor to Westinghouse E lectric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application March 25, 1937, Serial No. 132,956 14 Claims. This invention relates to the manufacture of electrical devices such as highewa-ttage incan descent electric lamps, power tubes, recti?ers, or other devices where metal contact elements are employed for the passage of heavy currents, and is a continuation~in-part of my application Serial No. 692,587, ?led October 7, 1933, now Patent No. (01. 176-32) 2 paratively heavy preformed base portion ill of glass or other vitreous material is provided. This cup comprises a bottom wall, a peripheral flange, and is provided with contacts or thimbles i i. It is sealed along edge E2 to a bulb l indicated in dotted lines, and adapted to enclose the light source or other energy-translating unit. The cup may be provided with an exhaust tube ill, through When making a high-wattage incandescent electric lamp, as shown for example, in the 10 which the bulb may be evacuated in the usual manner. Usually the cup is provided with rigid lviassie Patent No. 1,869,572, or the Howe Patent metal support members or lead-in conductors ill’, N 0. 2,010,084, it is desirable from an operative and to which electrodes or resistance elements such practical standpoint to provide relatively large 2,075,057, dated March 30, 1937 ‘ as tungsten ?laments, which be like the ?la metallic contact pins and considerable di?iculty has heretofore been encountered in sealing the 15 nient l and associated support members 2 and 3 of the Massie patent, or the ?lament 2 and asso pins in the glass wall of the bulb which forms part of the device. . It has been proposed to provide tubular con tacts, termed thinible seals, preferably closed at one end and having the opposite end provided with a thin-edged funnel shaped opening. These pins are sealed to the ‘wall of a bulb by ?rst bead ing the edges of the open ends with glass and then heating by means of gas ?ames to seal the head to the edges of suitably disposed openings. ciated support members 3 and 4 of the Howe patent, above referred to, are secured. The cup may, therefore, be constructed to include the in ternal structure or operating elements of the de vice and aconvenient method is, therefore, had for properly mounting the elements and for lo cating them within the bulb. When the cup is fused to the bulb the device is complete for the sealing-off operation. As above mentioned, it has heretofore been pro It is an object of the present invention to pro .25 posed to provide the metal thimbles with glass vide an improved form of base for a vacuum layers or beads to facilitate their gas-tight union device. with the bulb wall. In the present case, however, Another object of the invention is to provide this beading is dispensed with. a base with contact members held by internal The wall 55 of the cup is provided with aper seals. tures is of any desired number. rl‘he selected A further object of the invention is to provide embodiment of the invention includes two such a base with means for projecting into contact apertures, since two contacts are to be used. members for consolidation therewith to hold said Each aperture is provided with an outwardly ex members rigid, 35 tending tapered hollow boss or extension ll. This Other objects and advantages of the invention boss is so proportioned that it just enters and en will be more clearly understood from the follow gages the inner surface adjacent to a tapered edge ing description together with the accompanying 253 of the enlarged portion lb of a thim'ble El. drawing in which, This enlarged portion of the thimble forms a sur Fig. 1 shows a portion of a bulb, partly in sec rounding flared skirt and is integral with a tubu tion, with contacts or thirnbles sealed therein in lar cylindrical portion iii which serves as the con accordance with the present invention; tact proper and enters a socket for the passage Fig. 2 shows apparatus for holding a thimble in of electrical energy through the device when in position to be sealed to a bulb wall and means for operation. The side of each boss ll’ is preferably heating the glass; 45 about as thick as the wall l5, so that the hole Fig. 3 is a view similar to Fig. 2, but shows the glass after it has been softened and sealed to the edge of a contact member; and Fig. 4 is a modi?ed form of apparatus for seal ing a thimble to a bulb, in which the heater is disposed within the end of the thimble, and in which the thimble connects with the bulb in a through the enlarged portion of the thimble, de ?ned by the tapered edge ?él, is restricted, as shown, to correspond approximately with the in terior of the tubular cylindrical portion ill, where by a strong connection with the thimble is pro vided, while allowing for the reception of a lead» in wire l5’. That portion of each conductor ll’l’, adjacent the connection with its thimble ll, forms, with said thimble, a rigid metal contact slightly diiferent way. In devices of the character to which the present invention is most applicable, a cup-shaped com 55 terminal extending through its receiving hole 2,407,998 0 a 4 edge embedded or sealed in the wall 15' thereof, I6. rI‘he slrirt portion 18, because of its thin~ as in the embodiment of Figs. 1, 2, and 3, the boss ness, as illustrated, has elastic properties, per 3! for that purpose extending from said wall like mitting slight relative rocking of the contact the boss I‘! of Figs. 1, 2, and 3. member II with respect to the base ID. It will also be understood that, although the A support or socket 2! having apertures or embodiment of Figs. 1, 2, and 3 shows the en pockets 22 may be provided to hold each contact larged portion l8 of a thimble ll secured to the element in position so that the boss 11 may be wall IS with its edge portion 20 embedded or positioned, as shown in Fig. 2. In accordance sealed therein, yet the Wall 15 may have its boss with the present invention a local heat zone is i1 formed like the boss 3| of Fig. 4; that is, se 10 provided to soften the wall !5 and glass boss I1 cured to it by a conical portion, and the sharp or and cause the latter to wet or stick to the edge tapering edge portion 20 need only be secured to 23 of the enlarged portion iii of the thimble, the outer surface of the boss I1 and not embed while at the same time softening the wall l5 suf ded or sealed in the wall [5. ficiently to allow the edge 20 to be embedded or Whether or not a connection as shown in Figs. sealed therein, as illustrated in Fig. 3. In the 1, 2, and 3 or as shown in Fig. 4, is employed, may present construction a heat zone is created‘ by depend on the kind of glass used. If Pyrex (C. means of a resistance element 22' in the form' of Gui-‘7741) is employed, in which the coefficient of a helical coil which surrounds the tapered edge expansion between 20 and 320° C. is about 2i! and the contacting glass boss H. An insu lative baffle 23 may be provided to con?ne the H 32><10—", it is desirable to employ the connec tion illustrated in Figs. 1, 2, and 3, in order to heat for the purpose intended when current avoid cracks due to shearing action between the passes through the coil. Any suitable source of sides oi‘ the enlarged portion 18 of the thimble current supply may be used and a switch 24 may l l and the boss l1. However, when No. 705 glass be provided to open and close a circuit including is employed, in which the coefficient of expansion 25 conductors 25 and ‘26, attached to opposite ends is about 46><10—7. either type of connection may of the coil or resistance element 22'. Some al» be employed without any trouble. ternative source of heat may, of course, be em Although preferred embodiments of the inven ployed, for example, an oxy-hydrogen ?ame. tion are shown and described herein, it is to be When the respective parts are in position and understood that modi?cations may be made the glass boss has been heated to a sufliciently . therein without departing from the spirit and plastic state, a member 21 is moved downwardly scope of the invention, as set forth in the ap against the inner edge of the aperture l8 to firm pended claims. 1y press the glass against the edge 20, so that the I claim: sharp edge of the enlarged thimble portion en 1. An electrical device comprising a glass ves gages the outer surface of the wall I5, is embed 05 sel, an aperture leading from said vessel and de ded therein, and effects a gas-tight seal. fined by a hollow tapered boss extending from a The member 21 is disposed with its vertical axis wall thereof, and a metal contact member secured in alignment with the vertical axis of the con to said boss, said member comprising a hollow, tact member so that as pressure is applied to the cylindrical portion closed at its outer end, shoul member the contact pin is aligned with the axial 40 dered at its inner end, serving as the contact line of the tubular boss or extension ll. Thus, proper, and adapted to receive a lead-in wire as heat is applied to soften the glass to permit from said vessel through said aperture, and an it to flow onto the inner surface of the contact, enlarged portion extending toward said vessel the member 21, in conjunction with the support from said shouldered portion, the sides of said for the contact pin, maintains the proper perpen enlarged portion decreasing in thickness from dicular relation of the pin with the Wall [5. said shouldered portion to a sharp edge, said en In cases where exceptionally large contact larged portion flaring toward said vessel, ?tting members are employed, a heater element 21’ (see over said tapered boss and sealed only to the ex Fig. 4) may be disposed within the con?nes of terior thereof, the sharp edge of said enlarged an edge 28 of a thimble 29 and a glass boss 35. SU portion engaging said wall which is continued In this case a heater coil 32 may be carried on a outwardly therefrom at an angle to said contact sleeve 33, one end 34 being electrically connected member so as to effect a gas-tight seal. to the sleeve. The other end 35 of the coil may 2. An electrical device comprising a glass ves sel, tubular bosses extending from a wall of said be connected to a conductive member 36 suitably insulated from the sleeve 33. Electrical energy vessel. and cylindrical metal contact members having shoulders from which enlarged ?aring portions extend into engagement with said wall may be supplied from any suitable source and. a switch 3'1 may be employed to control a flow of current through conductors 38 and 39, connected and are disposed around and sealed to the ex to the sleeve 33 and member 35, respectively. When current flows through the heater element, 60 terior of said bosses to effect a gas-tight seal. 3. An electrical device comprising a glass ves the glass boss 3| is rendered plastic and wets the sel, tubular bosses extending from a wall of said edge 28 and a gas-tight seal is produced. Obvi vessel, and tubular contact members having ously, if found desirable, the structure shown in closed outer ends, intermediate shoulders, and Fig. 4 may be provided with an external heater coil to provide a surrounding zone of heat to fa C) O enlarged portions flaring toward said vessel, the walls of said enlarged portions tapering to thin cilitate the sealing operation. edges, ?tting over said bosses, extending to said In the present embodiment, the boss 3! does wall, and sealed to the outer surfaces of said not extend directly from the normally horizontal bosses. ‘ wall portion l5’, but is connected thereto by an 4. A base for a lamp bulb comprising a glass approximately conical portion 40, and the edge 70 cup de?ned by a bottom wall and peripheral 28 of the thimble 29 is not embedded in the wall flange, tapered hollow extensions on said wall, l5’, as in the previous embodiment, but merely and tubular metal contact members having extends to the conical portion 40. However, it shoulders and ?aring enlarged portions extend will be understood that, if desired, a large thim ing from said shoulders, said enlarged portions ble 29 may be secured to a bulb It)’ by having its 75 I 5 2,407,998 ?tting said tapered extensions, engaging said wall, and sealed to the outer surfaces of said ex ders from which enlarged ?aring sharp portions tensions. extend into engagement with said wall, and are disposed with said sharp portions sealed around the apertures to effect gas-tight union. 10. An electrical device comprising a glass ves sel, a Wall of said vessel having apertures and tu . 5. An electrical device having a vitreous wall provided with apertured portions, and metal con tact members, each extending in a direction sub stantially normal to the plane of an apertured portion, comprising a contact proper and a skirt bular contact members having closed outer ends, intermediate shoulders, and enlarged portions portion extending therefrom, ?aring toward said wall, and having a sharp edge portion surround 10 ?aring toward said vessel, the walls of said en larged portions tapering to thin edges sealed to and with the sharp edge portion sealed thereto the outer surface of said vessel around the aper tures. to e?‘ect a gas-tight union. 6. An electrical device having a vitreous wall 15 20 11. A base for a lamp comprising a glass cup de?ned by a bottom wall and a peripheral ?ange, apertures and sealed to said wall. 12. A metal contact terminal device for a bulb— wall base comprising a contact proper, a lead-in conductor portion adapted to extend through an aperture in said base, and a ?ared skirt taper 25 sel, a wall of between said device and base. 13. An electrical energy translation device comprising a vitreous envelope having openings therein, a plurality of metal contact terminals each comprising lead-in conductor portions pass ing through one of said openings, a contact prop a ?ared skirt extending therefrom, each 35 40 rigidity to support theterminals device. having su?icient 14. An electrical device comprising a vitreous vessel, a Wall of said vessel being formed with 45 9. An electrical device comprising a, glass ves sel, a wall of said vessel having apertures, and cylindrical metal contact members having shoul- - the sharp-edge a gas-tight seal. HENRY K. RICHARDSON.