[1]Patented June 16, 1925. 11542,00 UNITED STATES PATENT OFFICE. J'GHN E. SEDERHOLM, OF ST. PAUL MINNESOTA, ASSIGNOP, TO AMERICAN HOIST & DERRICK COMPANY, OF ST@ PAUL, XIN-TE,-,OTA, A CORPORATION OF MINNESOTA@ ELECTRIC RIVET HEATER, Application ILled August 5; 1922, Serial No. 579,940. To all qi@hont it M(7y concern: Be it Icnown that 1, JoiiN E. SEDFRHOI,,It, .t cit,ized of tbe United Stat,es, resident of St. Pgtjj, in tlie, coilnty of Ikai@@y and State of. Milinesota have invented cei-tain new and useftil. Improvements in Electric Rivet Heatei-s, of iN,Iiieh the following is a specificati(n. Tlii,-, inveiiti.on, relates to iiiiproveitieints in 10 electric heaters desi,-ned, I)artictilarly for lieatiiig 1-ivets for use in hot-i-ii,etin@,, striietur.il steel fraiiies for bitildings, bridges, ete. The prii-nary object of iny invention is to provide a 7@ivet lieater cal?able of beiiicr (Pei 15 ated to full c,,tpacity, contintiatisi and with y a hio,,Ii degree of efficiency. A fui-ther objeet of the inneiition i,, to provide a ri-,,et heater bavin- eacli of its se(,ondary Co,il-, or elements con,,tructed of oiie 20 piece, and, of practically an E f6rni, -,o ai to be in close, proximity with tlie, ina,-netic core, tbiis allowing practically all of the intignetic lines of force, set til) in the core liv the primary coils, to act upon sai(I coil-, 25 or elements'when t-he circuit is closed. A further object is to provide, ,t rivet hmter having removably mounted jaws, or contwt blocks for hol4inz the, rive,,ts, I so t,hat shoiild the conL%ct-, beeome daiiiaged 30 from wear,or arcing thev nitiy readilv -,tnd quickly be removed for replacenient: witlioiit disturbing the secondary elenients. A fiirther object is to provide, a I rivet, heater- capal,)@le of heating rivets of varioiig 35 lengtbs withoitt the neceisity of adj@i-,tTnents, and also one in which ti utimber of rivets mky be heated simtiltaneously. Other ohiects o,f the @ inve,,ntion will mo,re Place on the m,,i@,rnetic core and the iiieans for operating the rivet holdin 65 g jaws. Fi gure 3 is a top view slio-,viiig the genei-,(tl arrangeiiient of the diffel-ent, pirts. Figit re 4 is a longittidinal sectional -vie-,i, on the lide 4-4 of@: Figtire 2 and sliowing the, arran gemei)t of the pri,iyi,,try coils and the 60 secon diry eleiy)ents oi-i the iiiignetic core. Fi gtire 5 is -,t fra,-iyientai.-y vi(?iw,of the insiilite d joiiit oii one of the push i-ods for operat ing the tipper jaw sFi giire 6 is a wiring d,iagram of @the ,ip0 5 par,,ttt is. T n the ei-tibodiment of the invent'on beie shown , there is, disclosed, @i frame coii,.:isting of i@ paii- of froiit le-s 'i ,tnd rear Ikgs 8, pmfer ably of an(VIe l@l@'on. Tile frodt aiid 7(1 reai, .1e,7 oi-i,each side; are preferablv seciii-ed togetli er near tlie bottom by ti ei-os,, meiiil)e@ 9 riveted tliel-eto, tTid neai- the center s(,.ction by a tie-iod 10. A ma(,),netic core 11, constr iicted of litiiinate,(l slic 7.5 et,, -,teel@. erably rect-,tdgttllr 'li-i sliape is @ secill-ely clamped b@etweeii the front an(I le at gs tbe; top, b bolts 12, thlis providing a. ver@ y rtigged and stibst,,tntial frame. The upper and lower parallel longitudiiially extending n-iembers of t-he.@ i-nagnot.i.e core 11 ,ire covere,d witli a siiitable, iT@sul(,It-, in,- materitil 13. Oii tl-le iipper illei-nber Qf this core are inotiiited two priniar@, coils 14, oneadj,,teent, eacli end, while on 'the to)Yer 8 .5 itieriiber, ,tDd directly beiie,,itli the coils 14@ two sirnilar coils 15 are nioiinted. T o seconclai@y elenients 16, e w pr ferabiv of copper an(I of stibstanti.ally the letter E in 90 form, (Fig. 1)) are (-Iisposed iipoll the core 11, adjacent the primary coils, and are inful dwription sillated tlierefrom bv sheets of siiit-,iblp- in9 413 ftn ing,-,, and will be elsims: draw $close a . striietiire degi to ea the obiects t)f the "'tn-@ bilt @e llnA,ersto(A that the 45 invention i-, not confined to the e-,act, details or featiires sbowii, as variotis cha-ii,&es MR@y be, made witbin the, scope of the claims whic,h follow. In the drawitigs: A" Figure I is a. front elevation of an electric rivet heater embodying my invention. Figure, 2 is a ,tramverse -,eetional view 0 wcondar@y 4ements i stilating material 17 such a-s (,-,besto-s or i,n terposed betweeii said members, as.shiai,,,n in Figure 4. A bar 18, preferably (>f an@le 9t, iron, has it,,-, ends seclired to the re,,Ir of th6 frftme by bolts 19, with its 6entra:l @portion bea ri.ng a(Ylinst the rear faces of the seeondary eleiyieiits, thus, seciirp-ly clamping said elements @in their respeeti@,e Places iipon th'e loo magnetic core. This bar i.s. also i'nstilated from said elements bv suitable, instilation 21. Thp, objeet of forming the secondary elements as above described is t-o provid@ an 105 element which will snukly fit @t,lie Ignotti@ dinal ni mbpr of the coie. when mQ iinted
[2]1,542,008 thereoji, as slioivii iii Fi(,tii,e 2@ ti,iis Tli(, [Ni,o lo iiieretislil"r tlic, of tlc il-I it Si, ll,tl-e liere slioi,,-n 1,)tit, tAN7( , ) t e I II Ile sli,i,j't c@oils, T)Itt it 's to 1)(@@(Tals to tli(, 1)1,o,.I@s fo@ll- priiii, 5 be un@lei-stoocl. i!l 40 - e(I iii iiiii-ril,,,er ,,iid c.,i,,,e lei N"Il@i 1!1)oll lioiri,,,Ii Po!-,:,t,loll til(@ stop the size ai-i(I o.' tli(,, (It,- ol, t sire,d. l'be j)rimai- coils bei,e slio@-@-ii t") coiiiplc,tel,,.@ ejicii@(,,Ijllfl I]IC (@OFe SeCtiOlIS OTI ol, tll(@ tjlei, i@- e tIliS tl)(,I.e 75 The l'Ol'W,11'clly, exten(1;11(1 i,,pper iii(I f'oilo@yei@ 1)j-,iii(@lies oi' tli(, elei, i@o tl)(, ai,(, I)t-oA-i(le(I i-villi A-e;@ticzil oi.- iii(i also @i tlieii- stiiii f)f@lts TI (? cilre(I to tile 4 1(, 1-i,t t 11, 12; 1 T'(' ,ind projeeiiii,., foi,Ai,,,tr(llvtlii-oll(Yil cloli- 'r] 1 lo%"- 1(".' t (i t'L I -11 i),,ate(I @iperttii-e@; 1) '@'O,T (1,, d 'ii (@ojl("I@ (,tol. 1 to '11) (,Tlli(l(? ol@ till, (17 ce,,i-(,, the (,n(Is (,f-' @- li(, ()II 1- f) flie ]ill(, s@ii(I I)OIt@, @"11(i "1(,I(l :S (,oll@,ict, ,)Tocj@s 2')) 1)@- 2(; ))Ati@,, L 2@-. jl,,- flie the ti)(I -t@f)l. t , t,,Ict I)Ioelzs :lj.e 1,1,1,1 ;11 II Ille S I i I I I ,I se(@oli(',Ill,N' @it :,,I] tll)lcs. @ikii ll,,- I -o I I I: 1"() . ii-ai-(Ili- e tell(,Iill I c,@ i,@ ) N i" z I @,@i i ,,I il I I S N@- I ol' the j)locl@s 2' Foi, itF:(, @l 1, @f@st ()ll !I(, i@i i-cts. rT-'AN-o st@itiojiai@v cotit@ict J)lo(@l@s 2@) t,l,):s to Ill,,, i(Ill- to tll(@ 1)ol.i ;oils tll(, i@i@iiii I'Ti,,(, -wi@, eleiiieiits I))- Io f!l(' to 1),@ ill ti li"),o iiil)el. 1,ieat, @is f)li the iiid lo@@,(,ieoii'L@ict 2', S @N-itli the lti,,-s -,'S ill I)ol(lljl(,. loll(. 1"olt@ @is f slio@N-ii iii Fl(-til-0 1. (,oll(ll"""tol. to f,j.olll the Tli(@ al)on-c coiistiiti(,tiori ,l. i-ei-v si@- iteli 4C) tlij,oiio-ii tl)c, f@oii(Iii(,tol. (;.,) to tll(, siiiiple ztiid pi'acticillti iii(,;,Ljis foi@ si@-;tcli 4,,-), tli(,ii(,o tlii-ot,,Lrl) tli(, (- oTi(Itictoi- @) 7'). ai-id lioldin(,- the i:iA@(,ts tlie@- ,)G aii@T (,onclii(,toi@ to tile, lioate(l, ztii(I also slioiil('L iii@, of tl,,(? colit@l(@t iiiill) Iiii(@ 'll)(, "11)0"r(" (,i I-- I)IOCI@s I)ecollle (Ille t,() I,(, to @,,s tlit, o- t] I i I I T I )f@ st' repl@icei.iieiit tl,e lioll The t@N-0 ill)ldel. b@- of ll()ot -I)e(lils ")i), oil :I sli@tft 09. AvIii(@ll ol)ell 11111 (-lose 9 of the I)e,,Ials lia@,-e ibi-oli,--li en(,,i@@,izitioll ol, i,ll(, e-\tell(lillg @i7id iii tli(, to coiiiic@(,tiiil)l i-o(Is Tlit[s, A@-lieii ti)@@ is ill Colillectecl @it 3,I)@ tl-,e tl)e I)osit'oTi sliowii iii tl),e A-vii@iii@(i c,i,,cl., of sal(I 1)(,ino, pi,,,Ot,,illv (,()Illl(,Ctell ,,iicl the eoiltl.(\! siiil@eli -10 is )N-itli the conttet I)IOCI@s i,)i. of the savit@eli 68 )@-ill I I (, 1 @-) C). Tll' Coilecl te-lisio;) to feet(,(! bv the - f i - o i - , i t h e i , @ i ! i ' i i I i i ) ( @ lio',cl the (,ollt@l(,t I'loci@s tile i@-:ill I)e i@l, tf) the pe(l@ils ill tll(,@ii liol-illi@'i I)oS'tt;(,, SO(@ill'Ol to tll(' tll(@ foot P,'(I@ils P,2 f,@@oill ))Ost's tlieile(@, @@ze('t Av'ell @t -,-ii-et 'iisei-te,,l the I)ogts 7');, @vitli tll(, !)"icoiitact lilo,,,IT9 fo,, it iq iecess@!i@i7 i-nai,), coils 15. These I Fo to i-,istilate s:iicl IA)Iocks fi@o@ii tlic@ i)pflal coii- i)i-oA-ide(I 'witli tei.- inin@il I)osts iiectincr ro(is. This I ,,,s I)ciii,-), @oi,resl)oi,,diii- to tile tlil("e eolltli(,t ]@)OSts zl:i-. eff(,cteci 1))- Pi-o@-i@iiii,- -I zIS -i7.0 oji , ti@e, sNN-iteli 4,,-). Titlis i-od@@ the snvitel) .t@5 is in contiet witli the
[3]6 t F' d i@@@dd f6 heat' t'@ 6t whi6h,o@f6 f und-t6@ be@ ni@&ivm hea@,tl @6st@ 48"a@ sho*li' 1'li' lio, iv s@ 0 current Nvill flow fi-om,th6@eoil's'- 1'5"th@ou h- too loiig tb' be inseited b6twe"en thff bl6eks th6 Nvir'es 77 and, 78 fb@ a @ toriniii4l: p6st @t 9 aii(t' th6iiec tli,ioti&h'@ d coridtictoi@ 81 to the s wit(-Ii 08, coiiiplofing t&'in4@ditrm, hea:t ci@rcuit. The low: ia,iid Iiikli lieat primary etiits are siiiiilari@ coh@iect6d. Co@nliie@toi.- s@ 82 and 83' electrically ciyniiect tli@,,. c-dils@ 15 to tlie'switel-i@ 69, whln iiigh lieat, fiiid 10@ condiietor's 84@ and 85,60niii@et ttio@ co@il@ toi th@ si@itch 67 wlieil'l'ow heiit is@ requi@ed. Fr6in@tlie f6r6obirig, ther@f6re', it ivill ij6 iiotc@d that wlien the regulatin@@s*itch 45 is iii'@,ont,,,tct:witli thti, 16w-li4@h't poA rt Ecil of 15 the anipei-e . tiir'ns, of thLN,'Tirililia @oil@ 15,ivill ry be in eirettit v@hic@ Will, r6dtice th--, @ a!nip@titg I 0 fli)-%V in the co'ilg iitid' c@itiso, sA@d coil t-o becorrio, heate'd to' a@compttrittivoly 10'0 t6ilip4@ll:ttiii-e. Convei@@ely' Wlib@h th'o, swit@,li 45 is' 20 inov@d into;coiuei@ 'With the high:-Iieiit p68t if)@ i@ ritiMI)o@ 6f th6 iiiipcit ttiiii@r of the coils t5 b@t" etit oi@f of: fhe by inereasiiig the ampelta'glgitow,iw Aid@coils with tlie, r6sillt th@at @th@.Y bi@eoftio IleAt25 ed to, a retativ6ly hightt ternp4@@Aturo' oi., h i'g!h-he@:tt. TI@@ o oratio-n of thi-9: 'appitratus ih# be p ex'plaified is fbIloWg with i!Of#tOti'te to@ Figirro5 1 a:nd 6: 30 Fii-@t tlie i@e(,nit4find s@ivit@61i 4'5@ is k-tijii@,tol to@ the desi@6d We@rit. I h4ve IVOM stiovvn it in con,tAA@t,@ I'vith@ th4@ rtiOdi@i]3@f h 't f, 4 8.1 The, cofitrbl, Witdh 46 ii- tho@ti n n @o @6w t,'hr6tigl-i,'tiie iyiedi ing the c @ rie t i@ Lml 35 heat ptimEt@1-Y clieilit.-@ A@g th@ current passes tliroii(,-Ii the (,-oils 14 and 15, the magnetic core 11, oin which they are mounted becomes energized, said core in turn energizing the two secondary elements mounted thereon. The voltage in the secondary elements is very low, being norinally one volt, r less, but the 0 etirrent density vei-y high. dtie to the curreiit 'd' carrying capacity of sai elements Asstiniing now that a rivet is inserted between the 45 upper right contact bloek 23 and the stationarv block 29, (Figtire 1), the etirrent Will flow fi-<)m the block 23 throiigh the rivet to tl-ie block 29, thenee, arotind the, magnetic core 11 back to the block 23, thus form60 ing a, complete eireiiit around the core. (Figiii-e 6.) Owing to the inferior carrying capacity of the rivet due to its very low ciirrent density, it immedi.ately starts to heat. As,@oon as it lias attained the desired 55 degree of heat it is iemoved and the next rii,et inserted. Rivets inserted between the lower contact blocks 23 and the stationary blocks 29 are heated in a similar manner, the etirient pa,@sing from the block 29 through 60 the rivet to the block 23 thence, arotind I the 1 lower section of the core 11 and back to the blocks 29. This apparatus is also -,idapted to heat riv65 ets of considerable length without the,necessity of mechanical aajustments. If it is 29 a iid @ 23,@ they iii@ty be in-,efte@d 'between the stationary block 29 aiid the Iiig 28 pi-OAided oil the blov@able bl6(-,ks 23' t@- iiidi@ated ill 70 Figiii@ 1. Th6 o@e@,iti6n of the. l@o* and': i,, sililillti. t,<) tll.,it, of tliei iiieditim lieit dbove d(,s@rib,6d diff6riiii@@ oiily 1),v iiicreasin'g oidecreilsing the nuinber of' aillpel-(@'ttifiis@ iif thi@ @i)rilliai-y coi,1,8, 1,1),by ta,ppiii- T,5 said coi@ls; as@ he4@6in4efo@e desetibed. tlii.8@ illipt@oveti typ6 of i@ivet heliter, Pivets of Vtl.16tis diiiiiie@t@rs aiid lengtli8 iiiiy bohoated at oii6 time ttii,is (ri,eitly@ iiier0itsilig@ til@, tapti(!ity tjid@efficic@ii6@, of tlie; a@ppar,ttiis.' SO As lier6@ shonvn; tho, ii@agnetl6 c6ri@@ 11 is in, tho@ forn@-i of Ei rectangiflai@ fr-,tme,@ -,,%@ith tlie@ l@rilliary i@olls 14 aitang6d upoii ttlei uppet. longittidin6,1 jj:iethbei- 6f the,@ frartie, aiid th6@ @riifiafy coils@ 15 tipoil the lmV6t@ 86 lt)ngifudilivil@ iiieli! r@ of s'aid, ftiiiio,. Th(A E-,,4hilped@ soc6nd,tA:T@' eleiiients 16, 16, ar,t,@ etieli@ pi-t)vid@e4d' i#ith tliree br@.nelies 6.xt@--rid. ing Ett righ,t aii(YI6 to thi@ iiiai'n or back iiiei4b@6r there-6f. The; center hotizoiit@til 1)0 btan@,ii,oxteii4s b6twe6h@tlie ilppe,@ and 16wet- loiigi,tiidinal iheiiibe@ts@ of the core 11, while tfi@e@ uppet and lo-%@,e'r' br@'aiielie-,: thei@-- of e:kti6ifd oft'e a;bove tlie@ t'ipp@ er 16n(yitiidiii@,il U5 n'ieMt6t- afid; the othei@ bel6w tli6@ lower lbrigitudiiial iriem@ ber of sa@id core, 11. Si(lid btiinche's fit siittgly@ aoin@;t tlie, -,vttlls@ of the Cbr'e qs sholv@n: iri Figrtirc@ Eaelf o-f Sal sew rida@r"Y clernents@ may be 'd ' c@oiisid6red a , con tituti'ng'@@a do'@ible U-@slia,ped rneliiber, and the entire element is, therefore, of substantially E-shape. When a rivet is inserted, it completes a circuit either through the upper and middle branches of t-he second- 105 ary element,, or through the lower and middle branches o,f said elerrient, de ding u , pen Pon whether said rivet, is placed -,ibove or below the block 29. T
