US2558640A

US2558640A - Through conductor relay with detachable armature assembly

Info

Publication number: US2558640A
Application number: US31698A
Authority: US
Inventors: Wurgler John
Original assignee: Allis Chalmers Corp
Current assignee: Allis Chalmers Corp
Priority date: 1948-06-08
Filing date: 1948-06-08
Publication date: 1951-06-26
Anticipated expiration: 1968-06-26

Description

June 26, 1951 J. wURGLr-:R 2,558,640

THROUGH CONDUCTOR RELAY WITH OETAOHABLE ARMATURE ASSEMBLY 3 Sheets-Sheet l Filed June 8, 1948 June 26, 1951 J. wURGLl-:R 2,558,640

THROUGH CONDUCTOR RELAY WITH DETACHABLE ARMATURE ASSEMBLY 3 Sheets-Sheet 2 Filed June 8, 1948 June 26, 1951 RGLER 2,558,640

J. WU THROUGH CONDUCTOR RELAY WITH DETACHABLE ARMATURE ASSEMBLY Filed June 8, 1948 3 Sheets-Sheet 3 Patented June 26, 1951 THROUGH CONDUCTOR RELAY WITH DETACHABLE ARMATURE ASSEMBLY John Wurgler, Milwaukee, Wis., assigner to Allis-Chalmers Manufacturing Company, Milwaukee, Wis., a corporation of Delaware Application June 8, 1948, Serial No. 31,698

(Cl. 20G-87) 2 Claims.

This invention relates in general to improvements in relays, and more particularly to through conductor current relays.

Through conductor type relays are mounted so that a bus bar or cable passes through its magnetic core. For mounting the relay it is generally necessary to remove the frame and the armature from the core. In doing so the adjustments of the relay which determine its operating characteristics are disturbed, requiring the relay to be readjusted or adjusted only after it is installed.

It is therefore advantageous to use a through conductor type relay which can be disassembled for mounting the relay without disturbing any of its Operating adjustments. A preferred embodiment of such a relay comprises a balanced armature supported on a frame which is removably mounted on a U-shaped core. Another preferred embodiment is a relay comprising an armature pivoted on a leg of the core and supported on the frame when the frame is removed from the core.

It is therefore an object of the invention to provide a through conductor type relay that can be readily mounted on a cable or bus bar.

Another object is to provide a through conductor type relay which may be disassembled in two parts for mounting on the cable or bus bar.

Another object is to provide a through conductor type relay which may be disassembled for mounting on the conductor Without disturbing the adjustment of the armature.

Another object is to provide a through conductor type relay with a coil which may be slidably mounted on a leg of the core and readily removed when the frame is removed from the core.

Another object is to provide a through conductor type relay which may be mounted in any position.

Another object is to provide a through conductor type relay which is substantially shockproof in operation.

Other objects and advantages will be apparent from a consideration of the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a view in side elevation of a balanced armature through conductor type relay showing a coil mounted thereon and a normally open contact assembly;

Fig. 2 is a plan view of the relay shown in Fig. 1:

Fig. 3 is a right end view f the relay shown in Fig. 1;

Fig. 4 is a partial left end view of the relay shown in Fig. 1;

Fig. 5 is a view in side elevation of another through conductor type relay having a clapper type armature and a normally closed contact assembly;

Fig. 6 is a plan view of the relay shown in Fig. 5;

Fig. 7 is a right end view of the relay shown in Fig. 5;

Fig. 8 is a partial left end view of the relay shown in Fig. 5 with the cover broken away;

Fig. 9 is a cross sectional View taken along the line IX-IX of Fig. 6;

Fig. 10 is a View of the relay shown in Fig. 1 modiiied by addition of a coil thereon and by rearrangement of the contact assembly to provide normally closed contacts; and

Fig. 11 is a view of the relay shown in Fig. 5 modified by rearrangement of the contact assembly to provide normally open contacts.

Referring more particularly to the drawings by characters of reference, the preferred embodiment of relay illustrated in Figs. l to 4, inclusive, comprises a U-shaped magnetic core I2 having two legs I3, I4. Leg I4 is shorter than the other and has a iiat end forming a pole plate for one end of the relay armature. The longer leg I3 is provided with a rectangular slot giving a U- shaped appearance to the end of the leg. The bottom of the core is provided with a pair of drilled and tapped holes I6 for fastening the core in any suitable known manner. The core may be made with any required depth for mounting on bus bars of different predetermined sizes.

A frame of nonmagnetic material, such as brass, is mounted on the core. The frame comprises a plate I8 and a pair of spacers I9 integral With the plate for supporting the frame on the shorter leg I4 of the core. A pole plate or bridge 20 of magnetic material is seated on the leg I3 and bridges its slot to define an opening I5. This bridge 28 is fastened to the plate I8 by screws 2|. Screws 23 and screws 22 which pass through the bridge, fasten the frame to the legs of the core. Leg I4, plate I8, and spacers I9 define an opening 24 similar to opening I5.

Pivot supports 26 yare united to the plate I8 to form a part of the frame. The supports are located substantially midway of the two core legs, and each has a drilled and tapped hole 2l for receiving a threaded pivot member 28.

Each pivot member 28, besides the threaded portion, has a smaller cylindrical portion 3D, forming a pivot with a rounded or ball point l end. The pivot member is locked to the support comprises two pairs of fixed contacts 34 sup-Y ported on the frame, and two pairs of movable contacts 35 supported on the armature. A block 36 of any suitable known insulatingV material is fastened to the frame by screws: 2l, 22; The

block 36 is provided with four threaded studs 3'I for connecting leads thereto andfor'supporting Each .stud 31 is. locked in position by lock nuts 39; The lower" two pairs of fixed contacts 34.

end of each stud defines a xed contact 34, and is silver tipped to forma good Contact surface. Each studA 3'I may; alsoy be tapped for receiving a head screw, the head of which defines a fixed contact.

Fastened to armature 4I as by rivets 42, a sup-- port arml 43. of suitable. insulating material, eX- tends under the block 36. The support arm-43 carries a pair of resilientbridge contacts-35.each fastened by a screw 44 and nut A5 so that each pair ofbridge contacts35alignswithapair of the xed contacts 34. Each of the resilient bridge contacts comprises a pair of contacts-conductively connected together by aresilient bridge member fastened tothe arm 43. A shield 46 may be provided for the bridge contacts and may: besupportedl by the support arm 43 and fastened thereto byv screws II-provided0 with collarsfl between the ybridgecontactand the shield.

A transparent protecting cover #.8 is provided for the, contact assembly and is fastened to the block 36 by screws 49.

A nonmagnetic bar I is. attached to one end of the armature to balance the armature with thek movable contacts supported at the other end thereof.- The armature being balanced in all positions, therelay. isV shockproof in operation.

Al spring. 52 is seated in a recess 53 of plate I8, and the spring is-mounted on a threaded Stucl'SE-whichv is united with the'armature 4I.

The spring is.k held under compression between nuts 54 and the plate I8 for biasing armature -twoair gaps, one between armature 4I and the fendofk leg Il,and the other between the armature and bridge seated on leg I3. When the-armature is in the biased position Vshown away from the core, ther air gaps are relatively large and are called pickup air gaps; when the armature is attracted, the air gaps are relatively small and arecalled-the drop outairgaps.

The flux in thel air gapsat each end of the armature cooperate to ,givev a torque tending to pivot the armaturer in the same direction.

Also mounted in the frame are air gap adjusting screws 51, 58. Screw 58A is located in plate I8 for contacting the armature near'the short leg to provide a pick up'air gap adjustment. Screw 5'I is `located in plate I8extending through block 36, plate I8, and pole plate-Z'for contacting; the armature near the longer leg to provide a dropout air gap adjustment.

The relay may be provided with a coil 66.

' tached to the armature.

mounted on a leg of the core for either independent operation of the relay or diierential operation with the through conductor. The coil is constructed with an opening for fitting the leg of the core. A clamp 6I extending through the opening in the coil has bent up portions 62 for retaining the coil therebetween. Another portion 63 of the clamp 6I provides a hole for receiving a screw 64 to bind the clamp to the leg of the core. The clamp is also held to the core by the coil which it retains from longitudinal movement-on the core leg.

To' assemble the relay, pole plate 20 and the fixed Contact assembly comprising block 36 are mounted on the' frame and fastened thereto by

screws

21,22; The bridge contacts are mounted on the arm support which is permanently at- The armature mounted stud 55 is inserted into the hole 56 of the plate I8 and the armature is supported on the frame bythe pivots 30. whichare insertedinto the openings` in. the. opposite sides of the armature.. The pivots are pressed finger-tight against thearmature by turning the pivot members 28 in the supports 26. When the side play ofthe armature is taken up, the pivot` members are locked` by tightening` lock. nutsV 3l. BiasI spring 52 is inserted in recess. 53 over the threaded stud 55. The spring is compressed byv screwing lock nuts 54 on the stud. The set. screws 5l, 58, alsoprovided with lock nuts, are screwed into-the. plate. The cover l is mounted onblock. 36 toY protect the. contact assembly.

The coil. 6 may be. mounted on a leg of the core with the clamp previously insertedr in the coil.V The coil andclamp 6I. are slidably moved into position` on the. leg and the screw 64 insertedto hold the coilin place.

The frame then is mounted on the,4 core. with the bridger 2U seated on leg I3. and the. spacers I9 seated on leg Ill.

To properly adjust the relay, it may be test mounted and its core excited by predetermined values of magnetomotive` force. by a` conductor passing through the coreA or by a coil mounted on a core leg. Although the relay may be mounted in any position, for precise adjustment it is best to test mount it in the saine position it will assume in an installation in which it is to be'usedV When the armature is in the unattracted position, the pick up air gap is adjusted by screw 58 so that the armature is attracted by a predetermined value of'magnetomotive force fora given bias force on the armature due to spring 52. For a given pick up air gap and magnetomotive force, the bias of spring 52 is decreased until the armature is attracted to the core.

When the armature is in the attracted position, the drop out air gaps are adjusted by screw 57 until'the armature returns to the biased position shown for another predeterminedl value of magnetomotive force.

relay is not energized and make good contact when the relay is energized.

The relay, when thus properly adjusted, is ready to be mounted on a cable or bus bar; The

screws-22., 23 are removed, freeing the U-shapedv core I2 from the frame. The armature 4I remains supported on the frame and none' of the1 adjustments is disturbed. The U-shaped core I2;

s. is ythen suitably mounted on the cable or bus bar with the cable or bus bar intermediate the legs of the core. the core and the

screws

22, 23 replaced.

The relay may also be provided with a contact assembly comprising normally closed contacts as shown in Fig. l0. The plate I3 is provided with holes for receiving screws '2| for then mountn ing the block 3S on the other end of the frame. Blcok 36 is provided with a hole 4D for receiving stud 55 and spring 52. Studs 31 in block 36 are screwed so xed contacts 34 are brought near to block 36. Arm 43 supporting the bridge contacts 35 is mounted on the upper side of armature 4| at the end adjacent leg I4. The bar 5| is mounted on the underside of the armature at the end adjacent leg I3. The relay is adjusted as before except that the contacts are closed when adjusting the pick up gap, and the contacts are open when adjusting the drop out air gap of the relay.

The relay illustrated inl Figs. 5 to 9, inclusive. comprises an armature 61 pivoted on a leg 68 of, a U-shaped core 69. The leg 68 is beveled to form a knife edge fulcrum 18. and the armature has a notch 9|] cooperating with the fulcrum for pivotally supporting the armature on the core leg.

The nonmagnetic frame comprises a plate 1|, spacers 12, and an armature guard 13. The armature guard 13 is fastened to the plate 1| by screws 14, and the guard is spaced from the plate by collars 15 through which the screws 14 extend.

The frame is mounted on the legs of the core and fastened thereto by

screws

81 and 92. The armature is biased against the fulcrum by a spring 16 seated in both the armature and the plate 1| and positioned between them above the fulcrum.

Stud 18 is mounted on the armature 61 and extends freely through plate 1| and insulating block 82. `Over stud 18, spring 19 is mounted and seated in plate 1|. A stud 8| extending through block 82 is mounted in plate 1| and extends freely through the armature 61. Over stud 8| bias spring 83 is mounted and positioned in a recess in armature 61. Spring 19 biases the armature away from leg 80 toward its unattracted position against a stop r85 integral with plate 1| Stop `85 determines the pick up air gap of the relay. Spring l83 is mounted on the stud 8| with free play thereon when the armature is in the unattracted position. Spring 83 cooperates with spring 19 to bias the armature away from leg 80 when the armature approaches the lattracted position.

When the frame is removed from the core, the armature 61 is supported thereon. Bias spring 16 then forces one end of the armature against a rivet 11 in the guard 13, and spring 19 pulls the other end of the armature against stop 85.

Relay 66 is shown having a pair of normally closed contacts and `a pair of threaded studs 84 for connecting lead wires. Fixed contacts 86 and studs 84 are supported in block v82 which is mounted on the frame. Guard retaining screws 14 also fasten the block 82 to plate 1|. Theblock 82 is also bound to plate 1| by a pair of screws 81 which with screws 92 attach the frame to the core.

Bridge contacts 88 comprising the movable contacts of the Contact assembly are supported on an arm 89 extending from and attached to the armature. The contact assembly is also provided with a transparent cover 9|.

As in the case of the embodiment illustrated in Figs. l to 4, inclusive, the relay may be mounted The frame is again mounted on in any position and maybe test mounted and operated for adjusting the drop out and pick up characteristics of the relay. In the unattracted position of the armature it remains biased away from core leg V by spring 19 which determines the pick up of the armature. Spring 19 is adjusted so that a predetermined value of magnetomotive force will cause the armature to move toward core leg 88, taking up the free play of spring 83 on its stud. Further attraction of the yarmature compresses spring 83 as Well as continued compression of spring 19. Spring 83 requires greater force to compress it than spring 19. '.'CheV springs 19 and 83 are chosen with force characteristics which cooperate to bias the armature closely to the characteristic of the magnetic at? tractive force acting on the armature as the air gap decreases when the armature moves toward core leg 88.

When the pick up value of the relay is adjusted,

the stud 8| supporting spring 83 is turned to in.

crease or decrease the free play of the spring slidably mounted onthe stud between the head thereof and the armature. Decreasing the free play increases the bias and brings the drop out characteristic closer to the pick up characteristic. This larrangement permits the drop out to be adjusted Very closely to the pick up Value.

Removing the four

head screws

81 and 92 permits removal of the core from the frame on which the armature remains supported. The core may be mounted in a known suitable manner on a cable or bus bar, and the frame remounted on the core and the head screws replaced without disturbing the adjustment of the armature.

The relay may also be provided with a contact assembly comprising normally open contacts as shown in Fig. 11. For normally open contacts, two U-shaped brackets 93 are mounted on studs 84. Each bracket 93 supports a xed contact stud 94 aligned below a contact of inverted bridge contacts 88. The brackets 93 conductively connect the fixed contact studs 94 to the studs 84 to which leads are to be connected. The relay is adjusted as before, taking into account that the contacts are open when adjusting the pick up value of the relay, and the contacts are closed when adjusting the drop out value of the relay.

Although the relays herein described are referred to as of the through conductor type, they may be operated by at least one coil mounted on a core leg, or differentially operated by a pair of coils or a coil and a through conductor.

It is claimed and desired to secure by Letters Patent:

1. An electromagnetic relay comprising a U- shaped magnetic core having rst and second legs dening a passage for the insertion of a current carrying conductor, said first core leg being provided with a slot, a nonmagnetic frame removably mounted across said core legs to permit insertion of said conductor in said passage, a bridge of magnetic material mounted on said frame across said slot between said frame and said first core leg to denne an opening, a pair of pivot members mounted on opposite sides of said frame, an armature having a pair of recesses provided on opposite sides thereof at points substantially equidistant from the ends thereof, said pivot members engaging said recesses whereby said armature is pivotally positioned with one end extending into said slot of said rst core leg and the other end disposed adjacent to said second core leg, a stud attached to said other end of said armature and extending freely through said frameastinprz means. attacheftit'or thesendf of'i saidV studi. a; spring? tted;AA overt? said studi7 and. come pressed'betweensaid stopmeansandsaid iframey toc-bias' said armature, adjustable=screw:l means mounted on said"f.rame for vad;j1"1stingthe :air gaps between vsaid armature ends and saidy core legs, aa'rst member' of i' insulating material. attached tofsaid'fonewendof said amature and :extending through said; slot',Y a resilient bridge member Irounted^onsaidinsulating member, arstpair'of contactsrmounted on said' resilient bridge member and"'condctive'1y:connected thereby, asecond insuiating; member.;attached'to` said frame adjacent ter-said s1ot,"af second pairof contacts distinct v.from saids'crew 'i meansfmounted Aionrsaidecond insu-f lating memberand enga'geablez-with said -rstzpair oflontacts in response tto movement of said armae tureagainst 'theaetionof ysaid 'springpand means for adjusting the distance between saidrst and saidf second `pairv of"contacts When-userid' pairsfof contactsfaredisengaged:

2? Ani' electromagnetic relay operable: in respenseto therfl'ow of "current through aiV conductor;- said relayrcompris'ing a`` U lshaped magnetic eorefliavingistiand second 'legs defining a pas sagefor the insertionfof said conductor,` said first coreffleg. Abeing llonger than said 'second core'1eg and having'a slot at its end,` a-nonmagnetic frame removably mounted across said 'core 1egs"toper mit "insertion" of 'said conductor vin said: passage, pivot means mountedr'on' said: framaan elongated armaturesupported at a2 point. intermediate ythe ends'lth'ereof` on! saidipivot. means. to .form With said core a1magnetic circuit in which' magneticux is producedbysad ow'l'of currenteoneofthe endseof samiarmature: extending@ into: saidz slotand tire others'enti?.A of sax-idf; armature-e extending;- betweezrsaid: frame and-'isaid'second 'corelegfsaid second core; legir forming g afapole plate-f fonY said otherend of. sa-idf A, armature and defining., therewithY air *gap-einsam', magnetic .,circut, d and. a bridgeoffmagneticv materia1--secured-to saidirst core leg acrossfsaid slot l forminga,po1e p1ate ,for saidnonegend ,ofi-said armature A,and Ldeninggtheref with a. second air.A gap.insaidl. magnetic circuit, wherebysaidg ux; causes said. one. end of said armature Itofbe attractedatowardr'said bridgealld saidother,Y end of .l saidlraxmatur'eeto be kryattracted'l toward 4said:secondcoredeg.`A to. .cause,rotation ,Voir

said armaturezabout saidpivot means.v

JQHN .WURGLER- REFERENCES" CITED The@ollltlwing;` ref extensas?, are; of record 1 inf. the le of this patent:

UNITED STATES PATENTS Ray; Aug 7,"1 1945"