US1469208A - Switchboard lamp - Google Patents

Description

E. A. BOHLMAN SWITCHBOARD LAMP Filed Feb. 14 1921 Y 7 strip. of my invention associated with a lamp Patented @et 2, 1923.

- nutren srarss raar ,essie ERNEST A. BOHLMAN, or orrrcAeO, rLLrNOIs, AssrGNon'ro KELLOGG- swITonBoAnn AND SUPPLY COMPANY, or cHrcAGO, rLLINors, A CORPORATION or rLLINors.v Y,

SVIITCHBOARD LA MP.

'Application filed February 14, 1921. Serial No. 444,772.l

To all whom t 'may concer/rt.'

Be it known that I, ERNEST A. BOHLMAN, a citizen of the United States of America, residing at Chicago, county or" Cook, and State ot Illinois, have invented certain new and useful ImprovementsV in Switchboard Lamps, of which the following is a specication.

My invention relates to switchboarf lamps which are small in size and adapted to be mounted within small confined spaces. These lamps areused to a large extent for telephone switchboards and are mounted in banks. Switchboard; lamps et the above type are provided with terminal strips towhich the lead-in wires of the lamps are soldered, and these terminal strips contact with springs in the lamp jacks when a lamp is inserted therein to connect a lamp in the circuit in which it is desired to include it.

An object of my invention is the provision of an improved terminal strip for a switchboard lamp and means for' mounting the same, which is very economical to manufacture, very simple in construction and the use of it greatly facilitates the assembly oi the lamp, thus materially decreasing manufacturing cost.

For a more complete understanding of my invention, reference may be had to the accompanying drawing, in which like reference characters in the several views denote like parts, and in which Y Figyl is a perspective view of a'switchboa-rd lamp embodying the improved termina-l strip of my invention;

Fig. 2 is a disassembled perspective view of the lamp bulb, the lamp terminal strips and the base for the said lamp;

nal strips secured to the base of the ksaid lamp, andbefore the lamp bulb is inserted betweenfthe termina-l strips; t Fig. 4 is -an enlarged sectional view of the fr lamp, illustrating the terminal strips securing meansgrand Fig. 5`is a sectional view along theline 5 5 ofFig. 4. A

Referring now more in detail to my invent-ion as illustrated, I sho-w the terminal bulb L, which is preferably of the form shown in which the .end oi the bulb is round. rIhe usual iilament 2 is provided and is connected to and carried out through the side Fig. Sis a perspective view of the termiinsane walls of the lamp bulb L inthe usual man,-

ner by mea-ns of platinum wires,fthe ends v3 and 4 lof said wires being soldered to theV terminal strips 5 5. The Vmetallic contact strips or terminal strips 5 5 forming ter-` minals of the lamp arelpreferablyfof the form shown that is, they extend along the sides of the bulb L for some distance and are suitably Vshaped for aportion of their length to cause them to' closely fit the contour of the lamp, bulb L. rIhe terminal strips 5 5 are suitably cut and stamped of sheet brass, and as both terminal strips are similarly constructed, a description of one will be sufficient. Y v j A wooden base 7 is provided, whosebody portion 8 is cylindrical in shape, and its end 9 is beveled for purposes as will presently be described. The base 7 is provided with a central opening 10 extendingI the length of the base 7 and is 'of a size to receive the reduced end portion 11 of the bulbA L; the

said base 7 also serves as a mounting means for the terminal strips 5 5. Y The terminal strip 5 comprises a forwardly extending portion 6, suitable in shape to cause it to iit 'closely to the lamp bulb L, and itsrearward V.beveled portion 13 of the terminal strip5. The terminal stripl 5 isalso provided with a pair of clips 15, integrally formed therewith, vthe said clips 15 `being intermediate` of the ends of the terminal strip 5 andbein for purposes asfwill presently be describe To secure'the terminal strip 5to thebase .7, -therearward portion 12 or the vterminal vstrip 5 is placed over tlieicylindrical and beveled portions 8 an'd9 of the base .7 and slipped forward to cause thevt'ongue 14 of 5 tov enter the centralopening -10 of the base 7. When in this position, as illustrated .the end -ot thefbase 7 and the V-clipsl 15l are bent over .the edge of. and into therhollow,vv

10o the beveled portion18 of the terminal strip base 7 and'iirmly engagenthe circumferf 'Y entia-l edge 16 of the cylindrical portionof the-base 7, as clearlyy illustrated in Figs. 4 and 5. The said clips 15, in association i. movement of the terminal strip in relation to the base 7, and this method of securing Valso prevents side movement of the terminal strip,*thus producing a `rigid mounting of the said terminal strip to the base 7. vThe terminal strip 5 is also provided with an intermediate reduced .portion 17, and the inner face 18 of theV reduced portion 17 forms a; soldering face to which the platinum terminals 3 and 4 of the lampi-ilament are soldered.` rlhe terminals 3 and l are soldered to the face 18 and near the edge of thel respective terminal strips, there be'- -ing sufficient space between the reduced end of the lamp bulb L and terminal strips 5-,-5 to Apermit the soldering of said terminals to said terminal strips.

l/Vhe'n kthe terminal strips 5-5 are secured to the base 7, as `just described, the forward 'end portions 6-6 converge, as clearlyA illustrated in Fig. 3, and when the terminal ist-rips 5-5 are thus assembled to the base 7 Vtheyare ready to receive a lamp bulb L. A lamp vbulb L isinserted between the end Yport-ions. 6 6 of the terminal strips 5--5/Y with -redu'ced'end vportion 11 of the bulb L 'resting in the central opening 10 of the base 7. A suitable cement is placed on the end 11 of the lamp bulb L to secure said bulb Yto the' base 7. Cement is also placed on the yinner surfaces. of the forwardly extending` portions 6 of the terminal strips 5 to secure a lamp -bulb L to the terminal strips. In the former methods clamping means are ,provided to hold the bulbs in place between 'the terminals between the time that the Vcei'nent'is placed thereon until it has hardened by means of a drying operation, but with a terminal' of my construction this clamping' means is eliminated, as the bulb Lwhen inserted between the two terminal strip Vends 6 forces the free ends against their normal tension, and this tension Vof the terminalstrip ends holds the Vbulb L in place without any holding means during theV 'drying operation.

,l Thel ends 6 of the terminal strips 5 of `vthe 'assembled :lamp are adapted to be en- :ga'ged by contact 4springs of the lamp sockets, the latter being usually in the form oflamfp jacks comprising a pair of springs Y Vas iswell understood in theart, and 'a por- -tion of thisen'd 6 of theV terminal strip 5 Vis provided with a flattened ,surfaceV 21 to `.Y'provideag'ood contact surface between the e saidlstermi'nal strips 5- 5 :ofthe lamp and theccntact springs of lamp sockets, and this Y fiath'ess tendsfto prevent the lamps from be- 60 ing turned out vof their prosper position during'their insert-iomor thereafter; The beveled portionsfldof the terminal strips 5, for'm wedge facesse that when the lamp as a whole is inserted between the spring terminals of the lamp jacks, it causes the Meegos said contact springs of lthejaclrv to be spreadV apar'L to 'permit the ready insertion 'of the said lamp. The base 7 is provided with a pair of ribs 22 'diametrically opposed, for the usual purposes of 'separatien between the two terminal strips 5-5 secured to the base 7.

From the foregoing it is apparent 4that l have provided a terminal strip which is simple, complete and efficient in association with a. switchboard lamp, and it has been described with reference to a particular lamp construction, but it is readilyseeiiV it is applicable for other forms ofV lamps,

and that changes will readily suggest therm-` selves, and l, therefore, do not wish to be limited to the exact structure asshown and described, but aim to cover all such changes and modifications as come within the spirit and scope of the appended claims. Y

Having described myl invention whatl claim as new and desire to secure by Letters Patent is:

1. A terminal. strip of the 'class described'l comprising` a forwardly extending portion and an enlarged rear portion, artongue integrally formed with the rear portion of and j parallel'to said terminal strip', aV base pro# vided with a central orifice for receiving the.,4

tongue to position said terminal upon said base, a pair of clips integrally formed with said rear portion whereby said terminal strip engages the other end of said base, said clips engaging saidorilice in said other end in the same plane with said tongue. Y

2. A terminal stripV of the class described comprising a forwardly extending portion and an enlarged rear portion, a. tongue sheared out of the rear portion of said terminal strip, a base provided with a central orilice for receiving said tongue to position said terminal strip upon said base, a pair of means integrally `formed withsaidr enlarged rear portion and -intermediate of said terminal strip ends, 'said pair o=f' means turned baclrto engage said orice for securing said terminal strip upon said base. j l,

3. A terminal strip of the class described comprising a forwardly extending portion and a rear portion, an angularly Ydisposed tongue sheared out ofthe rear-portion of said terminal strip, al base .provided withV a Vcentral orificeV into which 'said ltongue eX tends Yfor positioning said terminal stripy orifice in saidbase for-securingsaid terminal strip to said base, another -tei'minal"istrip' mounted on said base like the jfirst, and a pair of non-conducting flangesv on said vbase separating said terminal strips.

4;. A terminal strip of the class describedY comprising a forwardly extendingV portion and a rear portion, an angularly disposed tongue integrally formed on said rear portion, a base provided with a Ycentra-1 orifice into which the said tongue extends, and a pair of clips integrally formed intermediate of the ends of said terminal strip bent to engage said forward end of said base to secure said terminal strip to said base, said base having a pair of non-conducting flanges and said terminal strip having its rear portion shaped to substantially conform with the contour of said base whereby said terminal strip engages said flanges to align said terminal strip, and to preventsaid termi* nal strip from rotating on said base.

5. A terminal strip of the class described comprising a forwardly extending and a rear portion, saidk rear portion having beveled portions, a tongue integrally formed with one of said beveled portions and a pair of clips integrally formed with the other beveled portions intermediate of the ends of said terminal strip, a base having its one end beveled and provided with a central orifice for receiving said tongue to position the said terminal strip upon said base and said clips bent to engage the circumferential edge of the forward end of said'base to secure said terminal strip upon the base aga-inst lineal movement, and a pair of flanges for said base, said beveled portions carrying said clips engaging said flanges to prevent rotation of said terminal strip upon sai base.

6. In an electric lamp terminal strip, a base element, said terminal strip having a tongue sheared out of its body near its rear end for extending into said base member, a

pair of flanges integrally formed with said rear end of Vsaid terminal strip for engaging -said base element to prevent rotation of said terminal strip on said base element, and a pair of' clips between itsends turned over to clamp said base member.Y

7. In a pair of electric lamp terminal strips provided with Vflanged portions, a non-conducting cylindrical base provided with an orifice and also having flangesto engage said flange portions of said terminal strips to insulate and align the said terminal strips, and three clips on each terminal strip to engage the orifice in said base on opposite sides of the flanges, part of said clips at the end of the terminal strips and part at interl mediate points thereof, said clips securing said terminal strips to said basje against line-al movement and said flanges engaging said flange portions to also prevent rotatable movement of said terminal strip.

8. In an electric lamp, a base of non-con-v duct-ing material in the form of a flanged cylinder beveled on both sides at the rear end, and terminal strips each having beveled ,i

side portions and a beveled end portion forv engaging the flanged beveled portions ofv said base, and mounted thereon each beveled end portion of said terminal stripshaving one clip to engage the rear end of the base and each beveled side portion of said termiward end.

Signed by me at Chicago, in the county of Cook and State of Illinois, Ythis 11th day of February, 1921. y i

ERNEs'r A. BOHLMAN.

nal strips having a clip to engage the orp

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