[1]United States Patent Office 31133@172 ARMATURE MOUNTING MLIANS FOR LiLECT170- MAGNETIC IZEALA@Y Willi@am A. Wiil;ams, Evaisville, Ind., znd Divight M. Hughey, Mount Carmel, Ill., assignors to American Mach@ne & Foundry Co., a corporation of New Jersey Filed Dec. 28, 1960, Ser. No. 79,065 5 Claims. (Cl. 200-87) This invention relates to electromagnetic devices and more particularl3t to electromagnetic relays. One of the objects of this invention is to provide an improved, comp-,tet, heavy duty relay. Another object is to provide a mtiltiple po'ie relay having means preventin.- arcing between adjacent poles. A further object is to provide an alternating current electromagnetic device with nieans to maintain quiet operation without excessive chattering. Still another object is to devise an electromagnetic device having an improved retainer bracket. A still further object is to devise a relay, of the type havin- a plurality of movable contacts carried by an armature, with iniproved means for connecting a plurality of flexible conductors to the movable contact arms in sucli a manner that the life of the conductors is not decreasedIn order that the manner in which these and other objects are attained, in accordance with the invention, can be understood in detail, reference is had to the aecompanyin.- drawings, which form a part of this specification, and wherein: FIG. I is an 6nd elevational view of a relay embodying the invention; FIG. 2 is an elevatioiial view of the other end of the relay shown in FIG. 1; FIG. 3 is a side elevational view of the relay ol' I-IG. 1; FIG. 4 is an elevational view, partly in seccion along line 4-4, FIG. 3, and with pprtions removed for clarity; FIG. 5 is a top plan view of the relay of FIG. 1, showing in horizontal section a cover enclosing the relay; FIG. 6 is a bottom plan view of t armature assem of the relay of FIG. 1; and FIG. 7 is a detail sectional view, on a-.i enlarged scale for clarity, illustrating the manner of attaching a flexibl-@ conductor to a movable contact arm of the relay shown in FIGS. 1-6. Referrin.- now to the drawings, the embodiment of the invention there shown is a four pole, double throw alterna'cin.- current relay comprising an L-shaped frame 10 supporting an alternating curreiit electromagnet 11 and an armature 12. Frame 10 is constructed from maa.netizable material and has a pair of mutually perpendicular legs 13 and 14. Leg 13 is provided with a plurality of struck-out mounting lugs @-5 by means of which the relay can be attached to a suitable support. As shown in FIG. 2, leg 14 has an upper end portion provided with a pair of aligned, laterally spaced bearing stirfaces or ed.-cs 16 which abut the boltom surface of the armature and provide a fulcrum about which the armature pivots between actuated and unact@,iated positions relative to the electromagnet. Ed.-es 16 are separat.-d by a shallow recess 17. Electi-omagnet 11 comprises a laminated core 18 secured at one end to leg 13 and supportin.- a spool 19 on v,,hich a winding or coil 20 is wound. Coil 20 encireles the core and is adap,ed to be energized with alternating clirrent. Core IS is of rectan-ular transverse cross-section, the upper end of the core being exposed and slotted to receive a shading coil 21 ivhich provides magnetic fields of different phase. As indicated by the dotted Iiiies in FIG@ 6, the shading coil is a rectangular annulus which encirc'les a shaded pole face 22 located between a pair of uiishaded pole faces 23. The long dimension of atented May'12, 1964 2 the exposed end of the core -,xtends transv,-rsely of armature 12. Elec'cromagnet 11 extends perpendicular to leg 13 and parallel to leg 14, the length of the electromagnet being such that the pole faces 22 and 23 and bearing edges 16 are approximately equidistant from le- 13 so that when the armature is attracted to its actuated position, it lies substantially parallel to leg 13. Adjacent to one end, the sides of armature 12 are notched, as indicated at 24 Io, in FIG. 6. A retainer bracket 25 is secured by a pair of rivets 26 to leg 14 and has a pair of ears 27 which extend through the iiotches 24 to prevent the armature from sliding laterally and longitudinally of edges 16. As shown in FIG. 2, each of ears 27 has an L-shaped 15 eiid poi-tion 28 which extends transversely of and overlies the armature to limit movement of the armature away f-roni engagement with edges 16, the direction of such movement being generally normal to edges 16 and parallel to leg 14. The end portions 28 are operative to prevent 20 the ears 27 from being withdrawn from the notches except upon rupture or permanent distortion of either the braclcet or the armature. Bracket 25 has a pair of lugs 29 wh@ich project outwardly from leg 14, the lugs being suitably shaped to 25 detachably anchor one end of each of a pair of parallel restoring springs 30. The other ends of springs 30 are detachably sectired to a pair of lugs 31 which extend from that end of the armature which lies opposite to electromagnet 11. Sprin.-s 30 are in tens@ion and exert 30 forces on armature 12 in directions parallel to leg 14 to bias the armatilre into engagement with edges 16 arid towaxd its unactuated position, such position being that illustrated in FIG. 3. As best seen in FIG. 2, bracket 25 and armature 12 are wider than leg 14. Lugs 29 and 35 31 are so located that the lines of force of springs 30 are separated by a distance greater thaii the width of leg 14 so that such forces are exerted on the armature @eyond the outer ends of edges 16. Projecting from the bottom surface of the arm-,tture is 40 a circular embossed or raised portion 32 which is dimensioned and arranged to abut only shaded pole face 22, when the arnlature is in its actuated positl:on, to provide an air gap between the armature and unshaded pole faces 23 for achieviilg maximum utiiity of the flux 45 coniponents. The positional relationship of the pole faces to the armature, when the latter is in its actuated position, is illustrated in FIG. 6. Secured to the end of leg 13 is a molded panel 33 of insulating material, the panel being a generally rectangu50 lar block which extends perpendiclilar to leg 13 and parallel to leg' 14., Panel 33 and le-. 14 are disposed o-9 opposite sides of the electromagnet. Armature 12 extends from leg 14 toward but terminates short of the panel. 55 Panel 33 is provided with four rectangular apertures 34. A pair of fixed contact arms 35 extends through eaeb aperture 34, the contact arms being spaced in a direction perpendicular to le.- 13. Each upper contact arm caxries a fixed, normally closed contact 36 and each lower 60 contact arm carries a fixed normally open contact 37. Also mounted upon panel 33 are a pair of terminals 38, to which are connected the terminals of coil 20, and four terminals 39 which are connected, in a manner de8cribed hereinafter, to four movable contact ariiis 40 car65 ried by the armature. The outer ends of contact arnis 35 and terminals 38 and 39 are each provided with a screw for attaching a conductor thereto, the ends being aiigularly arranged as shown in FIGS. I and 3 to provide con. venient access of a screw driver to the screws. 70 A rectangular insulating shim 42 aiid a molded mov I able contact arm cariier 43 are disposed on top of armature 12, being seoured thereto bya pair of rivets 44, th,-- lower
[2]3 ends of ivhich pass through and hold a pair of Belleville springs orv-iasl,@ers 45 against the armature. Carrier 43 includes a flat body 46 which, at its front end, has a dependent stiffenin-, lip 47 which abuts the left edge of the armature, es viewed in FIGS. 3 and 6, and a pair of laterally spaced, longitudinally exLe.1d;ng stiffening ribs 43. Along '@he re,ar @edge, i.e., &@e edge away from panel 33, carr-ler 43 has a transversely ext--ndiiig Lipstandin.- ridge, 41 provided witla four qpaced recesses 49 each of whioh receives the R,-,ed end of a different one of the mov@able con@tact arms 1,0. Each contact arm 40 is secured to carrier 43 by means of a compression pl@ate 50 and a rivet 51, the under side of the rivets :being insulated from the ar@nature by the insula,ting shim 42. The ridge 43 supports the fixed ends of the contac@t arms so that the free ends of the contact arms extend generauy parallel to body poition 46. -Each con'L@act arm is of electrically condlic-tive spring material alid carries at its free end a movable contact 52. E,ach movable contact 52 is disposed between a pair of normally open and normally closed fi--ed con@Lacts, the movable contacts and the fixed contacts being arranged to provide a four pole, doubletlirow, break-make switch. The contarts 36, 37 of each set of fixed contacts are @so spaced from each other that movem@--nt Of the armatLire between its actuated and unactuated positions causes the movable@ coritact arms to fi@-x and provide el.Tective wiping action betwee.1 thecon!tacts. When relays of the type thus far described are operated under conditions of heavy duty, there is a tendency for adjacent poles to are over. To prevent this, panel 33 is provid--d with thi-ce ribs 53 on the side thereof adjacent to the electromagnet and the arm,,tture. The ribs -are located between adj,acent sets of contacts and extend oat@@vardly from panel 33 a distance sufficient tO prevent arcilig between adjacent poles. T-he side ribs are aligned with stiffening ribs 48 of contact arni carrier 43. The center r-@b has an overhangin.- port@,On 54 whicli projects furtlier from the panel than do the sid@ribs and is engageable with a stop member 55 lom@@,ed on the forward edge of body portion 46. Portion 54 and stop member 55 are arranged to limit pivotal mo-,,eTnent of the armature in a direetion aivay from the pole face to a predetermined angle beyond @'Lhe uiactuated position o'L the armalure, slicii predeterm@in--d angle b-,ing so chosen -that, if stop member 55 is caused to abut portion 54, as by reason of shock during shipmept, for example, the movable contart arms 40 wilt not bc perni,ane-@itl@ distorted and thereby disrupt the initial -,idjustment thereof. It is obvious that the side ribs could be identical to the cenler rib and have overhanging portions also. Each of terniinals 39 is connerted to a different one of the mi ovable contac@'L arms 40 by nleans of a flexible str-,mded conductor 56. As shown in r@'IG. 3, each conductor 56 extends from its associatecl terni-inal 39 and has a loop, indicated at 57, which provides sufficient flexibili,ty to minimize interference with rpovemeqt oL Icile arm,,@),ture. If the ends of the iconductors were merely soldered to the movable cont,-act arms, the solder -vvould run between the strands of tlip- colicluctor into th-, area of the, loop and, upon solid,:fioation, shoi-ten the flexing le-.igth of the co-@iductor. Upder sucil circumstances, the solder not oiily decreases ti-@e ilexibility of each conductor q@nd slows jp movement o-f 'che -..YmaLL,.re, but it also weake,.is the cond,,ictor, at the po;nt w@ere the solder ends, so tha'L the conductor will eventually break at this point. To increase i,s life, each conductor 56 is a single Ion.-th of stranded wire,which is b.-nt at its middle and has the fr-.e ends secured to oiic of th-..terminals 39 by sold--ring, condiicto.-- 56 b--ing cove,-ed by a tubul@ar shealh of insulat@.ng material. As shonvn in FIG. 7, the looded end of conductor 56 extends through an eyelet 58 havin,an aiinular head 59 and a ttibular shank 60. The end of shank 60 wxiay from b-,ad 59 is criiiiped, or other3,133,172 wise distorted, the cr;mp being effec.Ilive to distort the looped end of the conduc:,or in such man-iier Li-at the portion of the conductor which extends beyond shank 60 has a greq@ler leleral dimension than thqt of the end of the crimp iso thal, the conductor cannot be puued out of or witl-idrav,,n from the eyelet. The eyelet, in tirn, extends thro@Ligli an openin- in a@id is soldered to the upstandirg end of the movable coiitact arm 40, the crir@ip being effective to preve@it solder from flowing back 10 through the shank onto th@ flexin.- ,)ortion of the conductor and thereby int@rfer'@ng Nv.;th movemeiit of the armature. Advan@ageously, the solder fills th.-,space indicat--d by tn.- dott---d lines in FIG. 7. As shown in FIG. 5, bracket 25 includes a lug 61 15 ext---.lds a@vay from leg 14 and is provided i@iith an aperture 62. A cover 63 is provided with a slot th-ough -,vhich lug 61 exteids, the cover being su,.tably shaped to enclose the compor@ents of the relay. A leaf spring 64 of angular configurat,@on is inserted tlirour,,h ai)e:iture 62 20 and beays agai-,i@.t iboth the cover and Lthe lug to bias the cover in@to enf,,agement with paii,-;l 33 and therely secure the cover in place. Panel 33 has a pair of recess-.s 65 O@ and the cov--r has a pair . pro,,@-.@,tions 66, indicated by the dotted lines in FIG. 5, which are received in re25 c,@sses 65, when the cover is in position, to prevent movement of the end o'L the @cover,adjacent the panel in a direction parallel to the plane of the pan@.I. )A7hen the relay is de-energized, the armature occupies an unactuated position, vihich position is ilIListrated in 30 l@'I G - 3. In the unaot,,ieted position, the forces of springs 30, v@tich tend to rotate armature ILZ in a clockwise direction, are balanced by @tli-- forces of the movable contact arms, wliich tend to rotate th@- ar@natare in a cGunterelo.k,vise direct;on. 'fli.- stifi-.icss ol' sprin.-s 30 ;s so chosen 35 aiid th@- movable contact arms 40 are so arranaed that the co-@itact pressur,@ atid the amount ol fiexin.- and wiT.)ing are eque@..l when tLe ai@matil-re is in eith,@r the actuated or uiiactuated position. When tltie rel,,ly is energizp-d by passiiig an al-ernating 40 cu.-rent te-ough coil 20, such current causes flux to pass through core 18, legs 13 and 14 and armature 12, v,,hereby the armature is moved, againet the bias of s rings 30, from the posi'@ion shown in FIG. 3 into enga@enient vvifn core 13, the raised portion 32 of the 45 armature then etiga.aing tli-- shaded pole face 22 in the mainer previously described. Movem-Int of the ar-r!,iature 12 from its unactuated position to its actuated pos@'@ti6-i c,,,uses movable coiitacts 52 to be first disen,@pged froiii the i-iormally closed fixed Co contacts 36 and the-@i eriga,@ed wi,h tle normally open 'ixed contarts 37, si-ich enga,-ement beii-ig accoinpanied by suitable ilexirig ol. the movable co-.itac' arlms to prop@, si--irfaces a-,id pr-,Vert stickerly wipe tt@e abutlin,@ contaCL ir@g thereo't. Subsecluer@t de-energization of the relay 55 allows sr-ring 30 to move the armalure to i,s unactuated position. A re'ay coiscrticted in accorclar@ce wi'll the foregoing descript@'@on is particularly oji:@et in o-rcration. It is believed t!aat this qa@--t oi-era'@icTi -is e,.ue to thre-- factors: d, allowiti@ 6o First, shading the iole face oll core 13; secon th.- armatur@- to eriga@,e only the shaded pole portion to provide ati air gip betwe-,n the armalure and the unshaded pole portio-@i wh--n the armature .s acluated; and third, provid-lnlq a tbi@ee po-'@nt s,,iso@-@ision for ',he armattire 65 Nvhe-,i in iis actu,,ited position, i.e., supporting the armature in engagement with thf, pole face a-@id the two sptced bearin.- ed.-es. NVMle only one embodiment of this invent:@on has becii shown, it ,vill be apparent to those skilled in the art that 70 niany changes can be made in the details and arrangenient of pnrts witliout depar,iilg from the scope of the invention as defl,,led ia the appended c'@aims. Vll%at is
