Патент USA US2404950код для вставки
July 3_0, 1946. R. c. DICKlNsoN l-:T AL 2,404,950.l >CIRCU'IT BREAKER Filed sept. 15, 1942 ‘ 2 sheets-sheet 1 [24 Z13 I @i laffe/2 July 30, 1946- R. c. DlcKlNsoN ET AL 2,404,950 CIRCUIT BREAKER Filed sept. 15, 1942 171g. 3. 2 Sheets-Sheet 2 ¿if 83 2, 213 insu/@Mw 211 insa/arjan .143 217 lll, 37 3.9 3.7 ZI! WITNESSES: 201 l 45 ‘ 43 ¿or ' and ffiz‘z [ff/ammazz BY Ã _Ã/ ‘ ATTORNE Patented July 30, 1946 2,404,950 UNITED STATES IPATENT OFFICE 2,404,950 CIRCUIT BREAKER Robert C. Dickinson, Wilkinsburg, William H. Stuellein, East McKeesport, and Fritz E. Flor schutz, Wilkinsburg, Pa., assignors to Westing house Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application September 15, 1942, Serial No. 458,358 18 Claims. (Cl. 20o-89) l This invention relates to circuit breakers and more particularly to a high-speed circuit breaker 2 nism, said latch being operable by the operating mechanism to close the breaker. ' which is operated to automatically interrupt the Another object of the invention is the provision circuit as a result of reversal of the current in the circuit controlled by the breaker. ' of an improved circuit breaker operating mech anism wherein the circuit breaker is held latched in closed position by a holding magnet which acts to hold a latch in a position to connect the movable switch member to an operating member, An object of the invention is the pro-vision of an improved circuit breaker which is operated at high speed to open the contacts and in which the contacts are trip free oi the closing means. Another object of the invention is to provide an improved circuit breaker in which the support frame for the breaker mechanism forms a part the latch being operable by a relatively small component of the opening bias of the breaker to release the switch member upon a predetermined reduction of the magnetic ilux. of the magnetic circuit for the holding magnet. The novel features that are considered char acteristic of the invention are set forth in Dar Another object of the invention is to provide a circuit breaker with an improved trip mechanism 15 ticular in the appended claims. The invention itself, however, both as to structure and opera wherein a trip magnet core member forms a part tion, together with additional objects and ad of the magnetic circuit for a separately ener vantages thereof, will be best understood from gized holding coil. the following detailed description of one embodi Another object of the invention is to provide a circuit breaker of improved construction which 20 ment thereof when read in conjunction with the accompanying drawings, in which: is safe and reliable in operation, and inexpensive Fig. 1 is a side elevational view, partly in sec to manufacture. tion, of a circuit breaker embodying the principles Another object of the invention is to provide of the invention; an improved circuit breaker wherein a pivoted Fig. 2 is a fragmentary sectional View taken on contact member is held in closed position by a 25 line II-II of Fig. 1 showing the structural fea latch member pivoted eccentrically of the contact tures of a portion of the magnetic structure of member pivot and movable substantially radial the trip electromagnet. ly to said pivot to release the contact member. Fig. 3 is a front elevational View of the circuit Another object of the invention is to provide 30 breaker. an improved circuit breaker with a novel latch Fig. 4 is a fragmentary elevational view, partly member which is movable longitudinally of itself in section, of the breaker in the tripped open to release a contact member and which is rotat position. able and longitudinally movable to reset posi tion. Another object of the invention is to provide a circuit breaker with an improved latch structure wherein a latch member which releasably con nects a switch member to an operating member is longitudinally movable to disconnect the switch member from the operating member and where in the latch member is rotatably and longitudi nally movable to reconnect said switch member to the operating member. Another object of the invention is to provide 45 Fig. 5 is a detail sectional view taken on line V-V of Fig. 1 showing the details of construc tion and mounting of the parts on the contact arm support shaft; Fig. 6 is a sectional view taken on line VI-VI of Fig. l showing the construction and mounting of the holding coil. Referring to Figs. 1 and 3 of the drawings, the circuit breaker includes a separable contact struc ture indicated generally at Il, an operating mechanism indicated generally by the reference character I3, a trip device I5, an arc blow-out an improved operating mechanism for a circuit breaker wherein a latch is movable by a trip de vice to eiîect opening of the contacts, the latch magnet I'I and an arc chute indicated generally being movable by the operating mechanism to breaker are mounted on a framework compris at I9. The several elements comprising the circuit close the contacts. 50 ing a pair of spaced upright support'bars 2I of Another object of the invention is the pro insulating material. The bars 2I are rigidly con vision of an improved operating mechanism for nected at their lower ends by an angle cross a circuit breaker wherein a latch is operable by a member 23 and a cross bar 25 disposed across trip device to effect opening of the breaker irre spective of the position of the operating mecha tical portion of the angle bar. The cross mem the opposite edges of the bars 2I from the ver el ber 23 and the bar 25 are clamped tightly against the support members 2| by means of bolts 2l which are disposed on opposite sides of each of the support members in order to maintain the proper spaced relation between the upright sup port bars. The upper ends of the support bars 2| are spaced apart and rigidly connected by means of a casting 29 having a portion 3| integral there with and extending transversely of the support bars. The transverse portion of the casting 29 extends beyond the upright bars 2i and is rig idly clamped thereto by means of bolts 53 dis posed on opposite sides of each of the support 4 the movement in one direction of the rod 83 and the contact. A spring 8S coiled about the sleeve 85 and compressed between the plate 59 and the arcing contact provides contact pressure for the arcing contacts. A flexible shunt con ductor 90 connects the stationary arcing contact 63 to the main stationary contact 6|. The movable contacts comprise a main mov able contact 9| and a movable arcing contact 93 (Figs. 1 and 4) carried on the upper end of a pivoted contact lever 95 pivotally mounted on a shaft 91 (Figs. 1, 3, 4 and 5) supported in the frame plates 3l. The contact lever 95 comprises a pair of levers rigidly connected at their up members 2| and which cooperate with a cross 15 per ends by an integral cross member 99 to which the arcing Contact 93 is secured by means of screws mi. The main movable contact al is secured directly to the levers 535. The contact lever Sli is biased in a clockwise or opening di rection by a pair of tension springs |93 (only vice l5 are supported in a frame comprising a one being shown) having one end hooked over pair of spaced parallell side plates 3l of magnetic a rod |65 mounted in the lower end of the con material which, at their left hand ends (Fig. 1), bar 35 and the portion 3| of the casting 29 to rigidly secure the casting 29 to the support mem ber 2| and to space these members apart. The operating mechanism i3 and the trip de tact lever and having their other ends anchored are rigidly clamped to the upright supports 2|. to spring studs iûl‘ projecting from the plates The right hand ends (Fig. 1) of the side plates 3l are spaced apart and rigidly connected by an 25 3l. The contact lever gli is also biased to open position by a pair of compression springs |99 angular cross member 39 secured to the side threadedly mounted on screws ||| and support plates 3l by means of screws (il. Referring to ed 0n the bracket 3S. Fig. 6 it can be seen that the side plates 3l are The contact lever 95 is releasably held in the clamped to their respective support members 2| by clamp plates ¿i3 disposed on the opposite 30 closed contact position by a latch member ||3 which is operated by the trip device l5 upon re sides of the support members 2| from the plates versal of the direction of current flow in the cir 3l, and securely held in place by bolts ¿l5 and lll. cuit of the breaker, to release the contact lever The plates 3l’ are supported at their right and permit the springs |03 and |69 to operate it hand ends by an insulating block 519 (Fig. 1) to the open contact position. The latch mem which is in turn supported on a channel-shaped ber ||3 is rotatably mounted on a short tubular member 5|, the block lle being secured to the cross member 3l) by screws 53 and to the chan nel member 5i by screws 55. A pair of spaced angle members 5l (Figs. 1 and 3) are suitably bearing H9 (Fig. 5) eccentrically surrounding the shaft 9i and supported in one end of a lever |2|. The lever |2| comprises a pair of spaced secured, for instance by welding, to the angle 40 levers pivoted on a pivot pin |23 mounted in the frame plates 3l. At its other end the lever |2| carries an armature |25 pivotally supported on a pivot pin |27 mounted. in the end of the lever |2|. IThe armature |25 cooperates with 45 an electromagnet H5 to retain the latch mem able base (not shown). ‘ ber ||3 in latching position as shown in Fig. 1,. The casting 29 mounted on the upper ends of and, as will be described later, the electromag the upright supports 2|, has a vertically disposed net operates upon the occurrence of reversal of plate 59 cast integral therewith and forming a current flow in the circuit of the breaker, to re mounting for the stationary contacts of the breaker. The stationary contacts comprise a 50 lease the armature. As shown in Figs. 1 and 5, the internal diameter of the tubular bearingL | I9 main stationary contact member 53| and a sta is substantially larger than the outside diameter tionary arcing contact 63. The main stationary of the fixed pivot shaft Sl. This permits the contact (5| is mounted on a block 55 of conduct tubular bearing H9 and the latch H3 mounted ing material which is slidably mounted on four cross-member 23 and to the channel member 5|, thus forming a rigid framework for sup porting the operating mechanism. The entire framework is adapted to be supported on a suit stud bolts 6l (only two being shown) threadedly 55 thereon to move up and down relative to the axis of the fixed shaft al. The tubular bearing engaging the plate 59 and extending horizon H9 is disposed eccentric to the íixed shaft Sl in tally from the face thereof. Electrically con the closed position of the breaker s0 that this nected to the back of the block 65, and me tubular bearing and the latch ||3 mounted chanically secured thereto, is a pair of flexible shunt conductors 69 each comprising, preferably, 60 thereon can move downwardly upon release of the lever |2| by the tripping electromagnet. a plurality of thin, ñexible strips of conducting A latch member |29 (Figs. 1 and 4) is adjust material. The flexible shunt conductors 59 are ably secured by means of screws |3| to a cross connected by means of bolts 1|, to opposite sides bar |33 connecting the two levers S5 which form of a conductor ‘i3 which is, in turn, secured by means of screws l5 to a cross member 'Il of the 65 the contact lever. The force of the springs |û3 and |99 tending to rotate the contact lever 95 casting 29. A spring 19 compressed between the clockwise, presses the lower beveled edge of the plate 59 and the iiexible conductor 63 provides latch member |29 against the upper left hand cor contact pressure for the main contacts when ner of the latch member H3 and tends to move the breaker is closed. A spring guide 8| is pro vided on the plate 59 to retain the spring la in 70 the latch member H3 in a clockwise direction about the tubular shaft HG. This rotation of place. the latch member H3 1s normally prevented by The stationary arcing contact (i3 is mounted on one end of a rod 83 slidably mounted in a means of a roller |35 mounted on a pin |31 sup sleeve S5 secured in the plate 59. The other end of the rod 83 is provided with a nut 8l to limit ported in a closing lever E39. It will be noted that the beveled latch surface of the latch member 2,404,950 5 |29 is inclined relatively to the longitudinal axis of the latch member I I3. This results in a down ward force on the latch member, which in turn produces an upward force in armature |25. Mo tion of armature |25 and therefore tripping of the 6 held in the position shown in Figs. 1 and 4 by the over-center condition of the toggle |5|_-|43. Referring particularly to Fig. 4, the contact le ver 95 is rotated counterclockwise from its open latch member I I3 is prevented by holding magnet position to the closed position by operation of the lever |43 which is accomplished by automatic ||5 until reversal of current as will be described closing means (not shown) but which moves the later. link |51 downwardly to close the contacts. Be The closing lever |39 is pivotally mounted on fore the contacts may be closed, however, the the shaft 91 (see Fig. 5) and is connected by 10 closing lever |39 must be retrieved and relatched means of an adjustable link |4| to an operating lever |43 which is pivotally supported on a shaft to the contact arm. The retrieving movement of the closing lever is effected by clockwise opera |45 mounted in the frame plates 31. The upper tion of the operating lever |43, the clockwise end of the link |4| comprises an eye bolt |41 movement of the lever being limited by a stop pivotally mounted on a pin |49 supported in the 15 |64 in the member 39. free end of the closing lever |39. The other end of the bolt |41 threadedly engages a yoke |5I, the two legs of which are pivotally connected to The clockwise or retrieving operation of the lever |43 is automatically accomplished by means of a retrieving spring |66 (Fig. 1) having one end the lever |43 by means of a pivot pin |53. A attached to the member 51 and the other end at downwardly extending arm |55 of the lever | 43 20 tached to the link |51. The spring |66 biases is pivotally connected to the upper end of a ver the link |51 upwardly and biases the lever |43 in tically disposed operating link |51, the lower end a clockwise direction, however the tension of the of which link may be connected to a power oper spring |95 is not su?licient to move the tog ated closing means (not shown). The link |4| gle |4I--I43 overcenter against the force of and the lever |43 form a toggle which, in the the springs |93-|99. When the latch |I3 closed position (Fig. 1) is slightly overcenter to is moved downwardly to release the contact le the Ileiît of the center line |49-I45. In this po ver 95 the pressure of the springs HB3-_|99 sition the force of the springs ID3-|99 transmit- ' is no longer applied to the toggle |4I--I43 ted through the contact lever 95, latch member whereupon the spring |99 moves the link |51 ||3, the closing lever |39 and link |4I, biases the 30 upwardly and rotates the lever |43 clockwise lever |43 in a counterclockwise direction against until it is arrested by striking the stop |94. Dur a stop screw |59 mounted in the angle mem ing the clockwise movement of the lever |43 the ber 39. toggle |4I-I43 is moved overcenter to the right When the electromagnet | I5 operates to release of the line I45---|49 to a collapsed position thus the armature |25, the springs IUS-_|99 act to ro rotating the closing lever |39 clockwise from the tate the contact lever 95 clockwise to the open position in which it appears in Figs. 1 and 4. As position (Fig. 4), and due to the beveled or in the closing lever I 39 is rotated clockwise, a cross clined edge of the latch member |29 a component pin |65 thereon engages the left hand edge of the of the force of the springs causes the latch mem latch member |I3 and rotates the latch member ber ||3 to move downwardly substantially radi 40 therewith until it clears the latch member |29 ally relative to the shaft 91 rotating the lever I2! whereupon the magnet I I5 attracts the armature clockwise about its pivot |23. The latch I|3 is |25 rotating the lever |2| counterclockwise and thus disengaged from the latch piece |29 thereby thrusts the latch member | I3 upwardly into latch releasing the Contact lever 95 from the closing ing engagement with the latch member |29. lever |39 whereupon the springs |93-|U9 quickly After the latch I |3 is reengaged with the latch move the contact arm 95 to the open position |29 it is held in its engaged position by the mag shown in Fig. 4. The springs |99 are normally net | l5 which is energized through the agency compressed between the member 39 and spring of the holding coil | |1, the holding coil ||1 being pads IIB (only one being shown) projecting lat energized independently of the current in the cir erally from the lower ends of the contact levers 50 cuit of the breaker. The breaker may now be 95. The springs |99 serve to assist the springs closed by rotating the lever |43 counterclock |93 in moving the latch ||3 to unlatching posi wise through the agency of the link |51 and the tion and in starting the opening movement of closing mechanism (not shown) to its position the contact lever 95. The springs |93 complete against the stop |59 (Figs. l and 4). This move the opening movement after the springs |99 have z ment of the lever |43 straightens the toggle reached the limit of their expansion as can be |4|--| 43 and rocks the closing lever |39 counter seen in Fig. 4. It will be noted that the movable clockwise. rï‘his movement of the closing lever contacts and contact arm 95 are tripped free of acting through the roller |35 rotates the latch the closing lever |39, i. e. the breaker will open member ||3 and the contact lever 95 counter when tripped even though the closing lever is held 60 clockwise to close the contacts and tension the in closed position. ' springs ID3-|09. The shock of arresting the opening movement Manual opening or tripping of the breaker may is dissipated by shock absorbers ||2, there being a shock absorber secured to the inner face of each of the frame. plates 31 engageable by the spring pads H9 as the contact lever 95 nears full open position. The shock absorbers may be of any suitable type preferably a spring biased plunger, be accomplished by opening the energizing cir cuit of the holding coil 293. The electromagnet ||5 (Figs. l, 2 and 4) com prises a plurality of laminated core members |51 each of which is provided with an air gap |69 (Fig. 2) and a smaller air gap |1| . The air gaps or of any suitable resilient material. As the contact lever 95 moves to open posi tion the latch member |29 rides across the upper |69 of the core members |61 are disposed alter nately on the upper right and left hand corners as indicated in Fig. 2. The core members |61 end of the latch member | I3 holding the latch I|3, the lever |2| and the armature |25 in their are suitably secured together to form a unitary core for the magnet ||5, and are also secured to end brackets |13 which are mounted between the moved position (Fig. 4). During the tripping action of the latch l| |3, the closing lever |39 is 75 frame plates 31 by means of bolts |15. Each 2,404,950 8 of the core members |97 is provided with a cen trally located opening |77 (Fig. 2) through which passes a conductor comprising a pair of parallel conductors |79 forming a part of the electrical circuit of the breaker. At its left hand end the conductor |79 is mechanically and electrically connected by means of bolts |89 to the inner end of a terminal connector |8|, and the right hand end (Figs. 1 and 4) of the conductor |79 is suit ably connected, for instance by brazing to a yoke |93 (Figs. 1, 4 and 5) of conducting mate rial. The yoke |93 has upwardly extending legs |85 (Fig. 5) each provided with an opening through which passes a sleeve |97 surrounding the shaft 97 (see Fig. 5) and having inner flanged ends disposed between the closing lever |99 and the legs |95. The legs |85 of the yoke |83 are disposed adjacent the inner sides of the contact levers 95 and are held in intimate contact with said levers by means of nuts |89 threaded onto the outer ends of the sleeves |97 and having spring Washers |9| disposed between the outer faces of the levers and said nuts |99. Each yof the nuts |89 is provided with a set screw |93 for locking the nuts in position after they have been rotated on the threaded portions of the sleeves |97 to provide the proper pressure con tact between the legs |95 of the conductor yoke |93 and the contact levers 95. The electrical circuit extends from the termi- :_x nal connector |92 through the conductor |79, yoke |93, the legs |85 (Fig. 5) cf the yoke, con tact levers 95, the main contacts 9|-9|, flexible shunt conductors 99, conductors 73, through the coil |9t of the blow-out magnet |7 to a terminal connector |95. As previously stated, the holding coil | I7 (Figs. l and 6) is continuously energized from an inde pendent source of energy and normally produces sufficient flux in the magnetic circuit to hold the „ armature |25 in attracted position. The hold ing coil | |7 comprises a core member |97 (Fig. 6) of magnetic material having one end threaded as at |99 to receive a nut 29|, also of magnetic material, and an energizing coil ing the core member. surround- ~- Ll After the coil 293 and the nut 29| are assembled on the core member |97, the assembly is inserted between the mag netic frame plates 97 adjacent the support bars the conductor |79 reverses its direction. The holding flux between the armature |25 and the magnet H5 is thus reduced to such a value that the armature is released and the springs |93--|99 move the contact lever to open position. The nut 97 on the left hand end of the arcing contact rod 83 (Fig. 1) is spaced slightly to the left of the portion 59 of the casting 2.9 in the closed position of the contacts so that when the Contact lever 95 moves to open the contacts, the main contacts Eil-9| will ñrst separate and then, a very short time later, the arcing contacts 63-93 will open drawing the arc between the arcing contacts. The arc resulting from the ñow of the current after the contacts have separated is drawn into the arc extinguisher |9 by means of the blow-out magnet |7 Where it is extin guished. The blow-out magnet comprises the coil |94, connected in series relation in the circuit of the breaker, and a U-shaped core member 299 of magnetic material supported on the casting 29 and insulated from the coil |94. The legs of the core members 299 are supported by vertically dis posed insulating bars 2| | having their upper ends secured by means of screws 2|.3 to the legs of the core member 269, the lower ends of the sup port bars 2| | being supported on the frame plates 37 and secured thereto by screws 2 I5. The arc extinguisher is of the slotted plate type and the current of the arc drawn thereinto is shunted around the contacts and the breaker operating mechanism to the terminal connection |S| by means of a shunt circuit shown in part at 2|7 (Figs. 1, 3 and 6). rThis prevents the iiow of current through the various pins, bolts and latches, which might damage them. The arc extinguisher is preferably of the type fully disclosed and claimed in United States Pat ent No. 2,242,905, issued May 20, 1941, to R. C. Dickinson and R. H. Nau, and assigned to the assignee of the instant invention. From the foregoing description it will be ap parent that there is provided an improved cir cuit breaker of novel construction which is op erated to open position at high speed in response to abnormal conditions and in which the con tacts are trip free of the closing means. It will also be seen that the trip device comprises a hold 2| (Figs. 1 and 6) and a retaining bolt 295 is ing magnet having a magnetic circuit which in cludes the frame members -for supporting the inserted through openings in the support bars 2|, the frame plates 37 and the core member. ‘breaker operating mechanism. Having described the preferred embodiment of The nut 29| is then rotated in a direction to force the end of the core member |97 and the nut into intimate contact with the adjacent frame ¢ plates 57. Nuts 297 0n the threaded ends of the retaining bolt 295 are then tightened to re the invention in accordance with the patent stat utes, it is to be understood that various changes and modiñcations may be made in the structural details disclosed without departing from some of the essential features of the invention. It is, tain the holding magnet assembly in place. It therefore, desired that the language of the append will thus be seen that the trame plates 37 form ed claims be given as reasonably broad interpre a part of the path for the magnetic ilux of the Ct tation as the prior art permits. holding magnet i i7, the iiux passing through the We claim as our invention: core member |97, one of the frame plates 37, 1. In a circuit breaker, relatively movable con the core members |97 and armature |25 of the tacts, a switch member mounted on a iixed pivot magnet H5, and through the other frame mem and movable to open and close said contacts, op (i5 erating mechanism for said switch member in ber 37 back to the core member |97. When the current is ñowing in the proper cluding an operating member operable to eiïect direction in the circuit of the breaker including closing movement of said switch member, a latch the conductor |79, the magnetic flux produced member having its free end interposed between by the holding coil ||7 in the magnetic circuit the switch member and the operating mem-ber and through the core members |97 and armature 70 for connecting said switch member to said oper |25 is in the same direction as the magnetic flux generated in the trip magnet | by the conduc tor |79. However, when the direction of cur rent flow in the breaker circuit is reversed the magnetic flux of the .trip magnet | |5produced by ating member, said latch being supported in dependently of said operating member and said switch member, a trip device including electro responsive means normally restraining said latch in latching position and being operable in yre 2,404,950 10 ' 9 sponse to predetermined circuit conditions to cause said latch to be moved to unlatching po to effect opening movement of said switch mem ber. sition to thereby effect opening of said contacts. 6. A circuit breaker comprising relatively mov 2. In a circuit breaker, relatively movable con tacts, a switch member mounted on a fixed pivot and movable to open and close said contacts, operating mechanism for said switch member in cluding an operating member movable to eiîect closing movement of said switch member, means interposed between said switch member and said 10 operating member for releasably restraining said switch member in closed position, said means be ing supported independently of said members, a holding electromagnet structure for holding the restraining means in restraining position, said holding electromagnet being operable in response to predetermined circuit conditions to permit lon able contacts, a switch member movable to open and close said contacts, operating mechanism for said switch member including a lever for operat ing said switch member to closed position, a latch member connecting the switch member to the operating lever to releasably restrain said switch member in closed position, means for pivotally supporting said latch member, said support means being operable in response to reversal of current in the circuit to effect longitudinal move ment of said latch member to release said switch member, and said latch member being pivotally movable with said operating lever to effect clos ing movement of said switch arm. 7. A circuit breaker comprising relatively mov able contacts, a pivoted switch arm movable to open and close said contacts, operating mech anism for said switch arm including an operating said restraining means being operable by said lever pivoted coaxially with said switch arm and operating member to move the switch member to operable to effect movement of said switch arm to closed position. closed position, a movable latch having an end 3. A circuit breaker comprising relatively mov able contacts, a switch member movable to an 25 interposed between said switch arm and said op erating lever to releasably connect said switch open and to a closed position to open and close arm and said operating lever, means independ said contacts, operating mechanism for said ent of said switch arm and said operating lever switch member including a member pivoted co for supporting said latch for longitudinal move axially with said switch member operable to ef rect closing movement of the switch member, 30 ment to an unlatching position means biasing said switch arm to open position and biasing said means for restraining said operating member in latch to unlatching position, and a holding mag closed position, a member supported independ gitudinal movement of the restraining means to a. non-restraining position to thereby permit opening movement of the switch member, and ently of said operating member and extending between the switch member and the operating member for normally connecting the switch mem ber to said operating member, and a holding magnet for holding said connecting member in connecting position, said holding magnet being net for holding said latch in latching position and operable in response to reversal of current in the circuit to permit said biasing means to move said latch to unlatching position and to move said switch arm to open position. 8. A circuit breaker comprising relatively mov able contacts, a switch arm biased to open posi operable in response to predetermined circuit conditions to permit movement of said connect 40 tion and movable to open and close said contacts, an operating member, a pivoted latch having its ing member from between the switch member and free end normally interposed between said switch said operating member to permit opening move arm and said operating member for restraining ment of the switch member irrespective of the said switch arm in closed position, means’ sup position of the operating member. porting said latch independently of said switch e, A circuit breaker comprising relatively mov arm and said operating memb-er, a holding mag able contacts, a switch member pivoted on a fixed net for holding said latch in restraining position, pivot biased to open position and operable to open said holding magnet being operable in response and close said contacts, operating mechanism for to predetermined circuit conditions to release said switch member including a lever movable to said latch, means on said switch arm for moving effect closing operation of said switch member, a said latch longitudinally from its position be latch member supported separately from said tween said switch arm and said operating mem switch member and said operating lever and eX ber, means to operate said operating member to tending between said lever and said member for eiïect pivotal resetting movement of the latch, releasably connecting the switch member to the said holding electromagnetic means actuating operating lever, said latch being biased to un said latch to its position between said switch arm latching position, means including an electro and said operating member while said switch arm magnet for holding said latch member in latch is in open position. ing position, said holding electromagnet being 9. A circuit breaker comprising relatively mov operable in response to predetermined circuit able contacts, operating means therefor, a mem conditions to permit movement of said latch ber interposed between the operating means and member to unlatching position to effect o-pening the movable contact to restrain said movable con movement of the switch member. tact in closed position, a frame for supporting 5. A circuit breaker comprising relatively mov said operating means, a trip device including a able contacts, a switch member biased to open "'~ trip member for pivotally supporting said re position and movable to open and close said con tacts, operating mechanism for said contacts in cluding a member operable to elîect closing of said contacts, a pivot-ally and longitudinally mov able latch member having its free end disposed between the switch member and said operating member for releasably connecting said switch member and said operating member, means oper able in response to predetermined circuit condi tions to cause withdrawal of the latch member straining member, and electromagnetic means for holding said restraining member in restraining position and operable in response to predeter mined circuit conditions to permit longitudinal movement of said restraining member from be tween said operating means and said movable contact, said supporting frame forming a part of said electromagnetic means, 10. In a circuit breaker- comprising a support ing frame for supporting the breaker mechanism, 2,404,950 il 12 for normally connecting said switch arm and said operating member, a trip member support ing said latch for rotary and substantially radial movement relative to the pivot ci said switch arm and said operating member, and electro responsive means operable in response to prede relatively movable contacts and operating mech anism for said contacts, a trip device including a latch member connecting the movable contact and said operating mechanism for restraining said movable contact in closed position, a trip member for pivotally supporting said latch mem ber and operable to permit longitudinal move ment of said latch member to a non-restraining termined circuit conditions to eiîect radial move ment of said latch to disconnect said switch arm from said operating member irrespective of the position of said operating member. l5. A circuit breaker comprising relatively position, and electromagnetic means including said supporting frame for holding said trip mem ber against tripping movement, said electromag netic means being responsive to predetermined circuit conditions to release said trip member. movable contacts, a switch member movable to open and close said contacts, operating mecha nism for said switch member including a. mem 11. In a circuit breaker including spaced sup ber operable to effect movement of said switch porting frames of magnetic material for support_ member to closed position, a latch' member having ing the breaker mechanism, a trip device includ one of its ends interposed between said switch ing a latch member operable to eiiect opening of member and said operating member to releasably the breaker, a trip member for pivotally support connect said switch member and said operating ing said latch member and operable to actuate said latch in a longitudinal direction to a non 20 member, biasing means at all times biasing said switch member to open position, auxiliary bias latching position, an electromagnet for holding ing means for biasing said switch member in said' trip member against tripping movement and opening direction during at least a. portion of the operable in response to reversal of current in the opening stroke, and a holding magnet for re circuit to release said trip member, said electro straining said latch in latching position and op magnetic having a magnet core mounted be erable to permit said biasing means to move the tween said spaced supporting frames, and a hold latch longitudinally to unlatching position and ing electromagnet having a core member mount to move said switch member to open position. ed between said spaced supporting frames for 16. A circuit breaker comprising relatively energizing said ñrst named electromagnet, said supporting frames forming a part of the mag 30 movable contacts, a switch member movable to netie circuit for said holding electromagnet. l2. In a circuit breaker, the combination of relatively movable contacts, a pivoted switch member biased to open position and movable to open and close said contacts, operating mecha nism for said switch member including a member operable to eiiect movement of said switch mem ber to closed position, a latch member interposed between said switch member and said operating open and close the contacts, an operating meni member to releasably connect said switch mem ber pivo-ted coaxially with said switch member ber and said operating member, spring means and operable to effect movement of said switch biasing said switch member in opening direction member to closed position, a latch connecting the and biasing said latch to unlatching position, switch member and said operating member to re leasably restrain said switch member in closed 40 said spring means being operable to move said switch arm to full open position, auxiliary spring position, a trip member for supporting said latch means biasing said switch member in opening for pivotal and longitudinal movement relative to direction and biasing said latch in unlatching said switch member, and an electromagnet for direction at least during the unlatching portion holding said trip member and said latch in re straining position, said holding electromagnet 45 of the opening movement of said switch member, and a holding magnet for holding said latch in being operable upon reversal of current in the latching position and operable to permit said circuit of the breaker to permit longitudinal biasing means to move said latch to unlatching movement of said latch to effect opening move position and to move the switch member to open ment of the switch member. 13. In a circuit breaker, the combination of a 50 pivoted switch member movable to open and closed positions, operating mechanism for said switch member including a lever pivoted coax ially with said switch member and operable to position. 17. A- circuit breaker comprising relatively movable contacts, a switch member movable 'to open and close said contacts, operating mecha nism for said switch member including a member move said switch member to closed position, a `trip device including a trip lever, a latch' member pivo-tally supported on said trip lever and having one end interposed between said switch member and said lever for normally connecting said switch member and said operating lever to re strain said switch member in closed position, and a holding electromagnet including an armature carried by said trip lever for holding said latch operable t0 effect closing movement of said switch member, means interposed between the switch member and said operating member for releasably restraining said switch member in closed position, means biasing said switch mem ber to open position, said biasing means acting through' said switch member to bias said restrain in connecting position, said holding electromag means in restraining position and operable to permit said biasing means to move said restrain ing means to non-restraining position and to move said switch member to open position, a, part of said biasing means being eiîective to bias said switch member to open position only during a net being operable in response to reversal of cur rent in the circuit of the breaker to release said armature and permit longitudinal movement of said latch to release the switch member. 14. In a circuit break-er, the combination oi relatively movable contactsJ a pivoted switch arm movable to open and close said contacts, an op erating member pivoted coaxially with' said switch arm and operable to move said switch arm to close the contactsy a latch pivoted eccentrically of said switch arm and said operating member ing means to a non-restraining position, and a holding magnet for holding said restraining portion of the opening movement of said switch. member. 18. In a circuit breaker, the combination of a pivoted switch member movable to open and closed positions, means biasing said switch mem ber to open position, operating mechanism for 13 2,404,950 said switch member including a lever pivoted co axially with said switch member and operable to move said switch member to closed position, a trip device including a tripping lever pivoted at a point spaced from the axis of rotation of said closing lever, a latch rotatably mounted on said tripping lever about an axis adjacent the axis of said operating lever, means connecting said latch for movement with said operating lever, a latch element on said switch member engageable 10 by said latch to connect said switch member and said operating lever, the engaging surfaces of said latch element and said latch being disposed so 14 that the opening force on said switch member tends to move said latch and tripping lever to released position to release said switch' member from said operating lever, and magnetic means for normally holding said tripping lever and latch in latching position, said magnetic means being operable in response to predetermined abnormal conditions to permit said latch and tripping lever to move to released position. ROBERT C. DICKINSON. WILLIAM H. STUELLEIN. FRITZ E. FLORSCHUTZ.