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Nov. 15, 1938. ‘v . ‘ G. A. HEALIS 2,137,001 CIRCUIT BREAKER AND ENERGY ABSORBER THEREFOR Filed Aug. 29, 1936 2 Sheets-Sheet INVEN TOR. BY A TTORNE Y. l ‘Nov. 15; 1938. V G, A__HEAL|$ ’ 4 ‘ 2,137,001 CIRCUIT BREAKER ‘AND ENERGY ABSORBER THEREFOR Filed Aug. 29, 1936 2 Sheets-Sheeiv @E .INVENTOYR. BY ‘@“wa'M ATTORNEY. ’ Patented Nov. 15, 1938 2,131,001 ‘ UNITED STATES PATENT OFFICE 2,137,001 CIRCUIT BREAKER sun ENERGY ABSORBER THEREFOR George A. Healis, Philadelphia, Pa., assignor to I-T-E Circuit Breaker Company, Philadelphia, ‘ Pa., a corporation of New Jersey Application August 29, ‘1936, Serial No. 98,582 21 Claims. (Cl. 200-166) My invention relates, to circuit interrupters, , double‘ function of displacing one friction mem~ circuit ‘ ber with‘respect to the other and of developing “ breakers, ‘and has for an object the provision of a simple, reliable and inexpensive means operable 5 in accordance withrthe amount of kinetic energy of the circuit breaker parts ‘for absorbing their energy to prevent rebound of the contact struc ture and deformation of the parts. My invention is an improvement upon the 10 arrangement described in co-pending application "particularly , to automatic _ high speed a substantial force which presses them against each other to increase the friction between them. , the opposition offered by the friction members. In one form of my invention the crank arm 10 supports one end of a spring which serves to Deans and assigned to the assignee of the present transmit and to apply to the friction members invention. , 15 stored in the movable parts of the circuit breaker is absorbed by friction developed between mem bers movable relatively to each other. By ab ‘sorbing their energy, the movable parts are rap idly decelerated and brought to standstill. The 20 time required to open the circuit is not decreased since‘ the deceleration of the parts occurs only after the movable contact structure has moved substantially to its open circuit position. My invention is particularly useful in connec- ‘ 25 tion with circuit breakers of relatively large cur rent-carrying capacity where the parts, because of the masses of metal necessary to carry the normal, and to withstand overload, currents, are necessarily heavy, and the opening speed is high. 30 Accordingly, with relatively heavy parts moving at high speed, the energy dissipated by suddenly , arresting movement of the parts, as by striking a fixed stop, which may be a part of the frame or one of the pivot pins of the circuit breaker, produces an impact force whose magnitude is many times that developed by a graduated but rapid deceleration of the members to standstill. As a result of the foregoing phenomena, exempli ?ed by the use of . the ordinary hammer, the 40 repeated hammer-blows on the stopping member not only caused its deformation but also transmit ted the hammer blows to the other parts of the circuit breaker, causing rapid deformation and excessive wear of their pivot pins and associated 45 is operativeiy associated with a friction surface in such manner as to increase with displacement Serial No. 98,276, ?led August 28, 1936, by William In accordance with ‘my invention, the energy 35 My invention is particularly characterized by 5 the provision of a crank arm one end of which parts. Further in accordance with my invention, hammeryblows or impact forces are eliminated by securing to one of the switch members suit able friction material and arranging a second member provided with friction material for slid ing movement thereover as the circuit breaker is the force of the spring developed in part by their relative displacement so that the opposition to movement increases with increase of displace 15 ment and with increase in the kinetic energy of the parts. For a more complete understanding of my in vention reference may now be had to the accom panying drawings in which: ‘ 20 Figure 1 is a side elevational view of'a circuit breaker embodying my invention with certain parts in section and certain partsomitted; Fig. 2 is a front elevation of a three-pole circuit breaker formed by three units of the type shown 25 in Fig. 1;' i i Fig. 3 is a perspective view of the actuating member of Fig. 1; Fig. 4 is a fractional side elevational view of the circuit breaker of Fig. 1 with some of the parts omitted and illustrates the position of the energy absorbing means after opening movement of the circuit breaker has been completed; Fig. 5 is a perspective view of the brake blocks of Figs. 1 and 4; 35 Fig. 6 is a side elevation of a modified form of the brake block. Referring to Fig. 1, I have shown my invention in one form as applied to a circuit breaker mounted upon an insulated base or panel Ill 40 through which extend studs or‘ terminal con ,nectors II and I2 ‘respectively connected to sta tionary contacts I! and II. To complete a cir cuit between contacts II and H, a bridging mem ber l5, consisting of a plurality of resilient or 45 spring laminations, preferably of copper, is sup ported on a movable arm l6, itself pivotally mounted on a pivot pin H for movement between open and closed circuit positions. ‘The pin I1 is supported by a pair of side plates i8, only one of which is shown. To relieve the bridging mem- - ber l5 from the duty of interrupting the circuit, opened. A spring normally biases one member in a position to'be engaged by a movable part of the circuit breaker, the engagement taking the upper end of the arm i8 is provided with an arcing contact l9 formed of arc resistance ma place along an inclined‘surface which serves the terial arranged to cooperate with an arcing con— 66 2 2,137,001 tact 20 electrically connected to the stationary 22, acting directly upon the knee-pivot pin 23 of contact i3. The arrangement is such that the contacts I9 and 20 are separated after separa tion of bridging member I! from its associated the toggle comprising link 24 and member 29 moves‘ the pin 23 toward the panel i0 and a strong contacts 13 and I4. clockwise direction. to move the arm I! in a The switch or circuit breaker operating mech anism may be of the type described in U. S. Letters Patent No. 2,025,781, granted December 31, 1935, upon application of W. M. Scott, Jr. 10 More speci?cally, the arm i6 is biased for move ment from a closed circuit position to an open circuit position by means of a powerful spring 22 connected at one end to a pivot pin 23 and at its other end to a suitable ?xed point, as shown, to 15 the pivot pin H. A double system of toggles, comprising toggle links 24, 25 and 23 pivotally connected together at corresponding ends by a pivot pin 21, cooperate to hold the switch mem ber It in its closed circuit position and also serve 20 to operate it from its open to its closed circuit position. The ends of toggle links 24 and 25 re mote fromthe pin 21 are, respectively, pivotally connected at 23 and 23 to an actuating member 29 and to the arm I‘. The ends of the links 26 25 remote from the pin 21 are supported from ?xed pivot pins 30 supported by the side plates i8. ' With the parts in their closedv circuit positions, as illustrated in Fig. 1, the pivot pins 21, 28 and 30 are in substantial alignment; the spring 22 30 tends to rotate the links 26 in a clockwise direc tion but their movement is prevented by the link component of its force rotates the links 23 in a clockwise direction and towards its open circuit - position.v Combined with the opening force of the spring 22, to produce extremely high speed movement of arm i6 and contacts I! and is to ‘open circuit position, are the forces due to the 10 resilience of the movable contacts and/or their supports. ' I ' , ' Circuit breakers of the type here under con sideration may be designed to carry current of magnitudes upwardly of 8000 amperes at 600 15 volts and to interrupt a possible short-circuit current of 400,000 amperes. ‘Consequently the parts are relatively heavy to provide sufficient mechanical strength and to carry or withstand large values of current. . 20 Because of the relatively heavy mass of the arm l6 and its associated movable parts, it will be readily understood the kinetic energy of those parts during opening of the switch is propor tional to the square of their respective speeds. 25 Moreover, since the maximum speed occurs as the movable contact structure l5, l6, l9 reaches its fully open position, the kinetic energy of the movable structure is greatest as it reaches its limit of movement. Heretofore the impacts, or 30 blows, delivered to stationary stops, in arresting 24, the actuating member 23 pivoted at 32, and by 'movement of the ‘contact structure, have caused v a latch 33 pivotally connected at 34' to member deformation of the stop members as well as defor ‘ 29 and engaging a stop 35 carried by a switch mation or excessive wear'of the pivoted portions 35 operating member 33. The pivot pin 23 occupies of the movable parts. The ‘result, was a short aposition just short of alignment with pivot pins ened life of the mechanism. There was also a 35 21 and 32. _ tendency of the parts to rebound,>in' some cases The force directly applied by the spring 22 to su?iciently to return the contact structure sub the actuating member 23 is resisted by the latch stantially to its closed circuit position. The re 33 but a component thereof tends to rotate the a suit was rapid burning of the contact surfaces and a failure of the circuit breaker to interrupt the overload or short circuit current in a time short enough to prevent damage to the conduc tors or to devices connected in the circuit. 45 by operating member 33, to prevent release of In accordance with the present invention, the the main latch. A second relatively light spring energy of the moving parts of the circuit-breaker 31a tends toretain the auxiliary latch 31 in its as they approach their limit of movement towards latch 33 to its unlatchedposition against the'bias of a relatively weak spring 33a. An auxiliary latch 31 pivotally mounted at" to the main latch 33 has a shoulder 33 engaging a stop 40, carried latching position. ' The operating member 33, biased by spring 22 50 through member 23 and latch 33 for rotation in' a counterclockwise direction, is latched into the position shown in-Fig. 1 by a latching member ‘I pivoted thereto at “a and engaging the hook shaped end of a member 42 secured to one of the 55 side plates i3. . To open the circuit breaker, a tripping mem ber 43 may be manually rotated about its pivot , circuit opening position is'rapidly dissipated as work required to move friction surfaces relative to‘each other. In this manner the moving parts are rapidly decelerated and brought to standstill without decreasing the opening speed of the cir cuit breaker. Deformation of parts, excessive wear, and tendency of the parts to rebound are substantially and effectively ' eliminated.v The latter feature, as pointed out above, becomes im portant when short circuit currents are inter- . 43a to release the latch 31 or it may be operated rupted because any return movement ‘of the con automatically in response to an electrical con- ;., tact members toward closed position decreases j 60 dition of the circuit. If the circuit breaker is to be opened in response to overload current of pre detemiined magnitude, an arm 44 pivoted at 45 may be attracted by a U-shaped magnetic struc ture, l3 ‘surrounding the stationary contact ll. 65 Accordingly, when su?lcient magnetic flux is produced by the ?ow of current through the cir cuit breaker, the arm 44 is rotated in a clockwise direction to move the tripping member. 43 against the auxiliary latch 31. Upon exertion of the 70 slight amount of force'necessary to release the - 1 auxiliary latch, the main latch 33, already biased to a releasing position, frees the movable contact structure for movement to its open circuit posi tion. ' > ‘ 1 - ' Upon release of the latch 33 the powerful spring the air gap between the contact structures and may delay extinguishment of an are drawn be 60 tween the contacts, or may result in re-ignition ‘ of an arc. . . As shown, the energy absorber and dlssipater comprises a brake block or friction member I] having secured to its upper and lower surfaces 65 friction elements 5| and 52 formed of woven fabric impregnated with a phenolic condensation prod uct though a good grade of automobile, or other type of, brake lining material may be used. The block‘ 50 is arrangedfor sliding movement be 70 tween two upstanding armsgll and I‘, Fig. 3, formed integrally with the actuating member 20, the surface 29a between the upstanding arms be ing machined to provide a smooth surface with 75 3 which“, the friction element II ‘cooperates. If desired, however, the surface Ila may be rough ‘ or otherwise formed to increase the frictional resistance. is a ‘ . a One end of the block . ll is wedge-shaped, V that is to say, it has an inclined face 80a while its opposite end is recessed to form a spring-seat for one end of the‘compression spring ll. The opposite end of the compression spring is, mount ed upon a spring seat carried by the lower end ' by an increased force applied by surfaceils to surface‘ lla. Energy absorbing and dissipating devices con structed as aforesaid have proved to be entirely satisfactory to bring the moving parts of a cir ‘ cuit breaker to a‘standstill with minimum shock. Impact forces or hammer-blows upon the piv otal connections were substantially entirely elimi-' nated. ‘ ‘ Continuing. with the operation of the circuit 10 51a of a crank arm 51 pivotally‘securedatjl breaker, as the switch arm Il reachm its fully to the arms 54 and 55. The opposite end, 51b of opened position, the brake block ll, by reason the crank arm nests within. a notch provided ‘of its displacement, has so greatly increased the in a plate 59 which slidably“ engages the fric pressure upon‘the friction surfaces, it is den-u tion element 52. It will be observed the spring nitely brought to standstill; ‘that is to say, the 15 .il normally biases the block 50 to a position in spaced relation ‘from the end 51a of the crank arm, or to 'a position near one, the forward, end of the surface 29a. ‘ I ._ _ The surface We is preferably inclined at an angle of approximately 52° with respect to the plane friction surfaces of elements 5i and 52, although the angle of surface liia may‘ vary sub stantially; for example, it may have a value . between 40°‘ and 770°,‘though‘ for special ‘cases .it may be selected either above or below these limits. As shown in Fig. 6, the block 50 may be ‘provided with a curved surface 500 formed so that lines tangent thereto form angles with the friction surfaces which vary‘ from about 70° to about, 40° as ,they approach ‘the lower part of ‘member 50. Again referring to ‘the operation‘ of the circuit friction forces after substantial displacement‘ of the block ll become so great. the block ll itself acts as a rigid stop, but since the 'major portion of the kinetic energy has already been absorbed, it is not, when acting as a stop, subject to blows 20 of a deforming or damaging magnitude. If some deformation of the inclined face or. surface lla occurs, operation of the circuit breaker is in .no ‘way affected. Moreover, when necessary, the block ‘ll may be readily and economically re 25 placed, although such replacement‘ is seldom ‘ necessary. I I i As shown in Fig. 6, the inclined surface lle is to advantage curved somewhat at its upper end so that the surface Ila initially‘causes a' relatively small displacement of block ll. The same result may be approximated by selecting _ the spring ll with characteristics such that sub breaker “to the openposition, it will be remem stantial initial compression of the spring does bered that as pivotpins 23 and 21 move inwardly . not transmit forces to the. crank arm as large as "toward the panel III, the actuating member ll for ‘later compression of the spring.‘ For ex ".‘rotates in a counterclockwise‘direction, ‘and the ample, several turns of the spring. particularly switch arm I6 moves rapidly in a clockwise di " rection towards its open circuit position. As the ‘may be ofless diameter thanthe remaining turns ‘ 140 rounded. surface Ila approaches the brake‘ block or friction member 50, the parts are arranged so ‘ that engagement between ‘the two‘surfaces Ila and 50a occurs at the upper. or rearward portion a f‘of inclined faceor surface "a. ‘ Subsequent movement of surface. Ila; upon the inclined face We displaces the brake“ block 50 and, applies to it a substantial force in ,a direction topress it ‘against the plane surface 29a‘ of ‘the actuating member. ‘The drag exerted upon plate 59 by movement of friction‘ material 52 is in a direc tion to rotate the crank arm I] in a direction to ‘increase the‘ pressure on the block 50. As shown in Fig. 4, as, the crank rotates in a counter clockwise direction, the for‘ce due to this effect becomes very great. The crank,due to the pro portioning of its parts, has a toggle-like or wedg ing action; that is to say, the braking force ap plied to the block. is many times greater than the force of the drag whichfenergizes the crank. (30 The spring 58, by displacement of the brake ‘block W, is compressed. and by means of crank arm l1 applies a pressure to the plate 59 simul taneously to increase the frictional resistance offered by the energy dissipater. Accordingly, the block is self-energized; that is, large friction forcesnare produced which do not depend upon the inclinationof surfaceliia. Moreover, when the parts are moving at greater speed, greater forces are exerted between the friction surfaces to increase the amount of energy absorbed. Spe those within the recessed end of the .block ll, of the‘ spring. With‘such an arrangement the 40 initial force transmitted would be much less per unit of change of displacement than after the time thersmaller turns of the spring engage each other to start compression of the turns of the spring having the larger diameter. The aforesaid selection of the angle of. the in clined surface lls rests upon the assumption the surface Ila' moves in a substantially straight line across and normal to the surface 500. . If the co operating surface, as surface Ila, approaches through a different path, the angle of ‘surface No is selected to produce the desired displace ment. ‘ ‘ ‘ Preparatory to reclosure of the circuit breaker‘ the latch ‘ll of the operating member ll is re- l leased.‘ during opening of the circuit breaker,‘ by movement‘ of a projection or roller 8!,‘ carried by member", over a cam surface lib. ‘ In order to reclose the circuit breaker an cper-. ating handlell, secured to the operating mem 60 ber ll,‘ is rotated in a counterclockwise direction until the stop ll is moved into a position ‘again to be engaged, by the main latch ll. this engage ment being ‘effected by the bias of the spring Ila. At the same time the auxiliary ‘latch 81 and the operating member ll are effectively‘ secured to the actuating member I! so that by returning the handle ll and member ll to their original positions, the circuit breaker is reclosed. Upon initial movement of the actuating mem ber" in a clockwise direction, the spring ll is effective to move the. friction member of brake block ll towards its original or normal position. cifically, the component of force, due to the in lined surface lilo, which presses block 50 against member" increases with increase in kinetic en ergy. Thus higher speeds of the parts result in In this connection, movement of block ll towards greater rates of acceleration of block ll caused its original position exerts a drag on the crank 2,137,001 II in a direction tending to decrease the pressure mechanical means operable in accordance with by the crank applied to the' block. the displacement of said one member for press ing said surfaces against each other with a pres ‘ > If the spring 56 is sufficiently strong; it may, vafter opening‘of the circuit breaker, rotate the actuating member 29in a clockwise direction to return thelbrake block 50 to its original position. At any rate the brake block W is returned tofits original position prior to reclosure of the circuit - breaker. . Thus thelenergy absorber and, dissi 10 pater is effective, should the circuit breaker be tripped during the reclosingvoperation, to pre sure which rises with the extent of displacement I of said one member. f 4. Means for absorbing‘ the energy of the mov able parts'of a_circuit‘ breaker incident to their movement from‘a closed to'an open circuit posi tion comprising relatively movable members, one of which is provided with a friction surface slid 10 able over a surface of the other member, means vent shock and injury to the parts.‘ ' operable by one of the parts of said circuit-breaker -The circuit-closing operation is complete as _ for displacing one of said members with respect soon as the latch‘ 4i engages the member‘ 42, al to the other, means operable ‘with a wedging though, as indicated, the circuit breaker is trip free; that is, it may be automatically opened . irrespective of, and without interference from, the operating member 36 and its associated handle 62. v , ' tween said members. ‘ From the foregoing it will be readily apparent that my invention‘ls applicable to circuit break ers of any number of poles. For" example, in Fig. 2 I have shown 'a three-pole circuit breaker, > each pole being identical with the one shown in Fig. 1. The actuating members 29 of each pole are connected together by a common cross member 65. Similarly the trip members N are secured together by a cross-member 66. ' The foregoing arrangement insures that an overload 30, upon one of the‘ poles of the circuit breaker is effective to trip all of the poles thereof to open circuit ‘position. ...The circuit breaker may be manually opened by means of a tripping member 61 secured to the cross~member 66. , action by one of'said ‘members to press said fric 15 tion surfaces against each other, and means for further increasing the pressure upon said sur faces in accordance with the displacement be - _ ' 5. Means for absorbing the energy of the mov 20 able parts of a circuit breaker incident to their movement from a closed to an open circuit position comprising ‘a pair of switch members having fric tion surfaces, one of which is slidable with respect to the other, and mechanical means energized 25 ‘ from one of said members for applying a pressure on said friction surfaces which increases in ac cordance with the extent of displacement between ' said members. 6. Means for absorbing the energy of the mov 30 able parts of a circuit breaker incident to their movement from one position to another compris ing a member provided‘ with a friction surface, means slidably vmounting said member upon one of the partsof said circuit breaker, said member While I have shown a particular embodiment , being provided with an inclined surface arranged of my invention, itwill be:understood, of course, to ‘be engaged by another part of said circuit that I do not wish to be limited thereto, since breaker for displacement ofsaid member as the many modifications may be made, and I there movable parts approach one of their limits of fore contemplate by the appended claims to cover movement, a crank arm, one portion of which co 40 ' any suchv modi?cations as fall within the spirit and scope‘ of my invention. What I claim is: ‘ operatively engages "said member to ,press said friction member against said cooperating surface, . > and a spring, associated‘ withpthe other end of 1. In a circuit breaker having contact struc said crank arm, operable on displacement of said 45 tures one of which is-moved relative to the other memberfor pressing said ?rst-named end of said from a closed to an‘ open circuit position, the , crank arm against said member to increase the combination of friction means comprising solid pressure between said surfaces. bodies in- sliding contact with each other for 7. I Means for absorbing the energy of the mov opposing opening - movement of said movable _ able parts of a circuit breaker incidenttotheir 50 structure, and mechanical means for increasing movement from one position to another compris , as a function of the speed and ‘displacement of ing a memberprovided with friction surfaces on said movable~ structure the opposition offered by opposite sides thereof, means having‘ a cooperat thefriction produced by the sliding contact be tween said solid bodies to said opening move ment of vsaid movable structure. 2. In a circuit breaker ‘having contact'struc tures one of whichis moved relative to the other from a closed to an open circuit position, the combination of friction‘ means comprising solid bodies in sliding contact with each other for op posing openingv movement of said movable struc ture, and mechanical means operable by‘ said movable structure for continuously increasing the opposition to said opening movement of said 65 movable structure by the friction produced bythe sliding contact between said solid bodies. 3. Means for absorbihg the energy of the mov able partsv of a circuit breaker incident to their movement from'a closed to an open circuit posi 70 tion compris..1g a‘ pair of relatively movable members one of which is provided with a friction surface slidable with respect to the surface of the other member, means operable by onelof the parts of said circuit breaker for displacing one 75 ‘ofsaid members with'respect to the other, and ing surface overwhich one of said friction sur faces is slidable, a brake block engaging the otheri‘of said friction surfaces, a crank arm, one end of which cooperates with said block, a spring associated with: the opposite end of said crank arm and operable by displacement of said. mem ber for simultaneously pressing said brake block and said adjoining friction surfaces against each 60 other. ‘ s, ,I . ‘ 8.‘In a circuit breaker provided with a mov able swltch member, actuating means therefor, the combination of means for absorbing the en ergy of the movable parts of the circuit breaker 65 incident to their movement from a closed to an open circuit position, comprising a member hav ing a surface slidable along a surface of said actuating member, at least one of said surfaces comprising friction material, means operable by 70 one of the partsof said circuit breaker for dis placing ,said member with respect to said actu ating member, and mechanical means for press ing said surfaces against each other with a pres sure which increases during displacement of said 75 , 2,187,001 member and which is substantially reduced upon one end of said block having an inclined surface, disengagement of said member and said dis- ‘ means biasing said block to a position where an placing means. upper‘ portion of said inclined surface is engaged 9. Means for absorbing the energy of the mov- . by said contact structure as the latter approaches . able parts of a circuit breaker incident, to their ‘its open circuit, position, further movement of movement from one switching position to ‘an other comprising a switch member having a fric tion surface, a second switch member having a cooperating friction surface and‘an inclined face adjacent one end thereof engageable by one of “said parts of said circuit breaker for displacement of said friction surfaces, and means for pressing said surfaces against each other with a pressure which increases with relative displacement of 15 said‘ surfaces. ' , 10. Means for absorbing the energy of the mov able‘ parts of a circuit breaker incident to their movement from one switching position to an other comprising a switch member having a fric tion surface, a second switch member, having a ‘said structure displacing one of said friction sur faces relative to the other, and a crank arm piv oted to said operating member, one end of said arm cooperatively engaging said brake block and the other end of said arm disposed adjacent the end of said brake block opposite its inclined sur face, said biasing means including a compression spring interposed between said brake block and vsaid last-named end of said crank arm. ‘14. In a circuit breaker having contact struc 15 ture movable at high speed from one position to another and an operating member for operating said contact structure to said one position, the combination of means for absorbing the energy of the movable parts of said circuit breaker dur cooperating friction surface and an inclined face ing its high speed operation comprising a‘brake adjacent one end thereof engageable by one of block having a pair of friction surfaces and‘ an said parts of said circuit breaker for displace inc‘ined surface at one end thereof and between‘ said friction surfaces, said operating member hav ment of said friction surfaces, a crank arm hav 25 ing its respective‘ ends cooperatively associated ing a‘ plane surface disposed between upwardly ‘ with said switch members, and a compression spring interposed between one end of said crank arm and said second switch member for increas ing the pressure between said surfaces in accord 30 ance‘with the‘ extent of displacement of said sec~ ond switch member relative to said first-named switch member. 11. Means for absorbing the energy of the mov able parts of a circuit breaker incident to their 35 movement from one switch position to another comprising a switch member having a friction surface, and an inclined face adjacent one end thereof engageable by one of said parts of said circuit breaker for displacement of said friction 40 surfaces, a crank arm having its respective ends cooperatively associated with said switch mem bers, and a compression spring‘interposed be tween one end of said crank arm and said sec ond switch member for increasing the pressure between said surfaces in accordance with the ex tent of displacement ‘of said second switch mem ber relative to said first-named switch member, said spring. upon disengagement of said inclined face from said part of said circuit breaker re turning said second switch member to its original position. 12. In a circuit breaker, an operating member for closing the circuit breaker, a means for open ing the circuit breaker, said operating member having a friction surface, a brake block having 55 a cooperating friction surface, a crank arm, one end of which cooperates with said block to press said surfaces against each other, one end of said block having an inclined face engageable by a movable part of said circuit breaker for displac 60 ing one of said surfaces relative to the other, and a compression spring supported between the op posite end of said block and the opposite end of said crank arm. ‘ ‘ 13. In a circuit breaker having movable con 65 tact structure movable to an open circuit, posi extending arms thereof and cooperating with one ‘of said friction surfaces, a‘ crank arm pivoted between said arms, a compression spring inter posed between one‘ end of said crank arm and said brake‘ block, and a pressure plate interposed between the‘other end of said crank arm and the other of said friction surfaces, one of said mov able parts engaging said inclined surface during said high speed operation to displace said block and to compress said spring. 15. Energy absorbing means for a circuit break e‘rcomprising a brake block, opposite surfaces of ‘which are lined with friction material, one end portion of which is wedge-shaped and a spring seat at the opposite end thereof, a movable part 40 of said circuit breaker having at least one sur face over which said brake block is slidable, a crank arm pivoted to said movable part, a spring supported between said spring-seat and one end ‘of said‘ crank arm for biasing the opposite end 45 of said crank arm against said block, and means engaging said‘wedge-shaped end to move said friction ‘surfaces relative to said movable part and to compress said spring, said crank arm trans ‘ mitting the force of said spring to said block to increase the pressure upon said surfaces in ac- ‘ cordance with the extent of relative movement of said surfaces. 16, A circuit breaker comprising fixed contact structure, a movable system including cooperat ing ‘contact structure movable to open circuit po sition, means for braking said movable contact structure comprising a braking member friction ally engaging and movable with respect to a co operating member, brake-actuating means in cluded in said movable system engaging and actu ating said first-named braking member with ap ' plication‘ thereto of a force having a component acting upon said first-named braking member in direction substantially corresponding with the di tion, an operating member, a toggle interposed , rection of its movement with respect to its said cooperating member, and mechanical means ac movable to, a collapsed position, means operable, tuated by said ?rst-named braking member for upon movement of said contact structure to open transmitting said force component and redi position, to move said operating member towards ; recting application thereof to said first-named between said member and said structureand , circuit breaker comprising a brake block having braking member to increase its pressure upon its 70 said cooperating member. 17. A circuit breaker comprising fixed contact a friction surface slidably movable over a coop 75 crating friction surface of said operating member, contact structure movable to open circuit position, 7; said structure, the combination of means for absorbing the energy of the moving parts of said structure, a movable system including cooperating 6 2,137,001 'means‘for braking said movable contact structure open circuit position and having components, one comprising a braking member frictionally engag of which acts upon said ?rst-named braking mem ber in direction to increase its pressure upon its ing and movable with respect to a cooperating member, brake-actuating vmeans included in said ‘said cooperating member, and another of which acts upon said ?rst-named braking member in movable system engaging and actuating said first named braking member with application thereto or avforce having components, one of which acts upon said ?rst-named braking member in direc tion to increase its pressure uponwits said cooper 10 ating member, and another of'which acts vupon said ?rst-named braking v‘member in, direction substantially corresponding with the direction of ' its'movement with. respect to its said cooperating member, and'mechanical means actuated by said "15 ?rst-named braking member for transmitting said second~named force component and redirecting application thereof to said ?rst'named‘ braking member to increase its pressure upon its said co operating member. 20' . 18. A circuit breaker comprising ?xed contact structure, a movable system including cooperating contact structuremovable to open circuit posi tion, means for braking said movable contact ‘structure comprising arbraking member friction 25 ally engaging and, movable with respect to a direction substantially corresponding with the direction of its movement with respect to its said cooperating member, and mechanical means ac tuated by said ?rst-named braking member for transmitting said second-named force component 10 and redirecting application thereof to said ?rst named braking member to increase its pressure upon its said cooperatingmember. 20.’ In a ‘circuit breaker having ?xed contact structure and a movable system including coop erating contact structure movable to open cir cuit position, the combination of a braking mem ber frictionally engaging and movable with re spect to a cooperating member, brake-actuating means included in said movable system engaging and displacing said ?rst-named member relative to its cooperating member after substantial cir cuit-opening movement of said system, and means including a pivoted arm operable by said displace ment 'for increasing the pressure between said members rapidly to increase the braking effort cooperating member, brake-actuating means in cluded in said movable system engaging and ac ' opposing opening movement of said system, and tuating said ?rst-named braking member with means operable during circuit-closing movement application thereto of a force whose magnitude of said system for producingra return movement of said ?rst-named member, said means includ 30 30 is dependent upon the speed at which said mov able system moves to open circuit position and ing said pivoted arm upon initiation of said re having a component acting upon'said ?rst-named turn movement being effective greatly to reduce the braking e?ort opposing said return movement. braking member indirection substantially corre 21. In a circuit breaker having a movable sys sponding with the direction of its movement with tem including contact structure biased to open 35 respect to its said cooperating member, and me chanical means actuated byv said ?rst-named circuit position, the combination of cooperating braking members at least one of which is dis , braking member’for transmitting said’ force com ponent and redirecting application thereof to said placeable with respect to the other member, ?rst-named braking member to increase its pres~ brake-actuating means included in said system sure upon its said cooperating member. ' 19. A circuit breaker having ?xed contact struc ture, a movable system including cooperating con tact structure movable to open circuit position, means for braking saidmovable contact‘ structure 45 comprising a braking member frictionally engag ing and movable with respect to a cooperating member, brake-actuating means included in said movable system engaging and actuating said ?rst named braking member with application thereto engaging and producing said displacement of said 40 one member, and means for increasing the brak ing effort quickly to bring said system to stand still comprising a pivoted arm for pressing said members against each other, means exerting a frictional drag upon one end of said arm to pro duce with respect to its pivot altoggle-like or wedging action greatly to increase with said dis placement the pressure of said members, one against the other. or a force whose magnitude is dependent upon the speed at which said movable system moves to GEORGE A. HEALIS. ' CERTIFICATE or CORRECTION. - I, November l5, 1958. Patent No. 2,157,001.v GEORGE: A. HEALIS . It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, first column, line 57, claim 11, afterthe comma and before the word "and" in sort --'a second switchinemberhavingacooperatingfriction surf'ace-—; page ‘6, second column, line 58‘, claim 21, for "member" read “members-e; and that the said Letters Patent‘ should be read with this correction therein that ‘the s'amevmay conform to the record of the case in the Patent Office. Signed and sealed this 28th day of January, A_ D, 191,1. _ (Seal) Henry Van Arsdale, Acting Commissioner of Patents.