US633773A - Circuit-breaker. - Google Patents

Circuit-breaker. Download PDF

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US633773A
US633773A US71023099A US1899710230A US633773A US 633773 A US633773 A US 633773A US 71023099 A US71023099 A US 71023099A US 1899710230 A US1899710230 A US 1899710230A US 633773 A US633773 A US 633773A
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breaker
circuit
arms
pivot
pin
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US71023099A
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Gilbert Wright
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00Details of electromagnetic relays
    • H01H50/64Driving arrangements between movable part of magnetic circuit and contact
    • H01H50/643Driving arrangements between movable part of magnetic circuit and contact intermediate part performing a rotating or pivoting movement
    • H01H50/644Driving arrangements between movable part of magnetic circuit and contact intermediate part performing a rotating or pivoting movement having more than one rotating or pivoting part

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  • brackets 11 which may be parts of a single employed for automatically opening electric casting, the base of which may be suitably 6o circuits when the current therein exceeds a fastened to the panel 1 by means of bolts expredetermined amount, which are generally tending through the part 8. If the circuitknown as circuit-breakers.
  • the object of my invention is to provide a natii'lg-current circuits, the parts 8 and 9 circuit-breaker which shall be simple in 0011- should be laminated; but for direct-current structionand effective in operation and which circuits they may form integral parts, remay be more easily and certainly locked in spectively, of the brackets 11 and the arms operative position and released from such 10, if found more convenient or desirable. position when the conditions of the circuit
  • the arms 10 are provided with upwardly- 2o demand it than has been possible in devices projecting lugs or ears 10, having openings 7c of this character heretofore employed.
  • Figurel is a l joined by a transverse bar 12.
  • a single arm side elevation of one form of circuit-breaker l2 projects from the middle of bar 12 and is constructedin accordance with myinvention, provided with a scale 13, a weight It, and
  • Fig. 25 and Fig. 2 is a front elevation of the same, with a screw 15 and thumb-nut 16 foradjustthe circuit-breaker being in closed position in ing the weight longitudinally on the arm both figures.
  • Figs. 3, 3, and 3" are perspec-
  • the main movable contact member of the tive views of certain details of the locking circuit-breaker comprises a bundle of curved and releasing mechanism, and Fig. at is a delaminae 17, which are bolted or riveted to a 30 tail view of one of the stationarycontact-tersupporting-arm or pair of arms 18, the ends minals and adjacent parts.
  • Fig. 5 is a botof the laminae 17 being free to be deflected as tom plan view of another form of circuitthey are pressed against the faces of the stabreaker, the cover being removed and parts tionary terminals 2 and 8. being broken away.
  • Fig. 6 is a transverse For the purpose of making tinal contact 5 sectional view of the device shown in Fig. 5. with the upper terminal 2 I provide a small Referring now particularly to Figs.
  • 1 to l plate or block 19 and mount a small contactof the drawings 1 is a non-conducting baseblock 19 upon the upper end of a spring-plate plate or support which will ordinarily be a 20, this plate being securely fastened elecswitchboard-panel of slate, marble, or similar trically and mechanically to the laminated 4o material.
  • the stationary contact-terminals contact 17.
  • the plate 20 is extended down- 0 2 and 3 are mounted upon the face of the baseward below the lower end of the contact memplate 1, and each is provided with a stud at, ber 17 and is of such length and of such form which projects through the base-plate in oras to make contact at all times with the face der to connect with abus-bar (not shown) at of the lower contact-terminal 3.
  • the sup- 45 the rear of the switchboard.
  • the two main contact-terminals 2 ally mounted at their lower ends upon a rod and 3 are in vertical alinement, and the up- 18, which is supported by the brackets 11 per one of these terminals has an upwardlynear the base, as shown.
  • I extending arm 5 having a socket or holder 6,
  • a movable contact-block 21, of carbon or 50 in which is mounted a block 7, of carbon or other substantially infusible material, correrco Lil spending to the stationary block 7, is mounted in a socket 22 on the upper ends of a pair of arms 23, which arms are pivotally connected to the upper ends of the arms 18 by a pin 23.
  • the arms 23 are provided with extensions 23", which project downwardly and inwardly beyond their pivotal support and are connected with the supporting-brackets 11 or other stationary portions of the devices by means of coiled springs 2-1-.
  • the operating or closing handle 25 of the circuit-breaker is mounted upon a lever-arm 26, which comprises a sleeve 26 and two arms 20, projecting therefrom inwardly.
  • the sleeve 26 is located between the outer ends of brackets 11, and it is pivotally mounted upon the pin 10.
  • a toggle-lever arm 27 extends between the pivot-pin 23 and a pin 27, located in the free ends of le ver-arms 26 The parts are so adjusted that when the circuit-breaker is closed the joint between the arms 2o and 27 of the togglelever is slightly beyond the dead-center-i.
  • the closing-lever 26 is provided on its under side with a lug 28, that projects toward and within a short distance of the arm 12, so that when the current through the circuit-breaker increases to such an extent as to set up a magnetic flux that pulls upon the armature 9 suflieiently to overcome the pull of weight 14 the arm 12 will strike against the lug 2S, and thus throw the toggle-joint downward below the line connecting the centers of the two pivotpins 10 and 23".
  • the springs 24, acting in conjunction with gravity, will throw the movable members of the circuit breaker outward and downward and away from the stationary contact members.
  • pivot-pin 23 which are located in arms 18 and 23 are cylindrical and are loosely fitted into the said parts.
  • the middle portion of this pivot-pin is partially cut away to form a knife-edge portion 23, and this knife-edge rests in an angularcut-away portion of a bushing 23, the angle between the sides of which is greater than that between the sides of the cooperating knife-edge portion, (see Fig. 3,) so that the two parts may turn with reference to each other without friction until the toggle'joint has passed its dead-center, when there is no longer any danger of binding be tween the parts on account of pressure exerted.
  • pivot-pin 27 which are located in the ends of lever-arms 26 are cylindrical, and the middle portion, which is located in the end of lever-arm 27, is partially cut away to form a knife-edge portion 27
  • This knife-edge portion is located in an angular recess in a bushing 27 the angle between the sides of the recess being greater than that between the sides of the knifeedge portion 27 for the same reason as that stated with reference to the bearing 23. (See Fig. 3.)
  • pivot-pin 1O which are located in the ears and in the sleeve 26 are cylindrical in form, and the portions which are located in the brackets 1.1 are partially cut away to form knife-edge portions 10.
  • I provide bushings 10 for the cut-away portions of the pivot-pin 10 each of which is cut away to form an angular recess, the angle between the sides of which is greater than that between the inclined sides of the pertions 10 for the reason stated with reference to bearings 23 and 27. (See Fig. 3.)
  • Figs. 5 and G the form of circuit-breaker here shown is designed and intended especially for use on railway-vehicles, and the operative parts are therefore inclosed in a casing 1 instead of being mounted upon aswitchboard.
  • the stationary terminal 29, to which main conductor 30 is connected, constitutes one terminal of the actuating-coil 31 of the circuit-breaker.
  • the other terminal 29 of the coil 31 is eleetricallyconnected to the movable member or blade 32 of the circuit-breaker, the latter being pivotally mounted upon the said terminal29.
  • a spring 33 here shown as coiled around the pivotbearing 34 of the blade 32, but which may be of any desired construction, is provided for throwing the movable member or blade outward when it is released.
  • the other main conductor 35 is connected to a terminal block 36, in which is mounted a laminated contact member 37, having a beveled free end and located in a position to be engaged by the edge of the blade 32 or with a suitable block or plate 32, set in the edge of said blade.
  • the terminal block 36 is also provided with two plates 38, which are either of resilient material and somewhat flexible, so as to spring to permit the end of the blade to enter between them, or loosely mounted and pressed toward each other by means of springs of suitable construction, these devices being enr- ITS is mounted upon a pivot 40 and is joined to the movable member 32 of the circuit-breaker by a toggle-lever 41,0ne arm 42 of which is rigid with the handle and the other arm 43 of which comprises two plates or bars spaced apart in order to receive at one end the free end of arm 42 and at the other end blade 32, the connecting means for the respective ends being pivot-pins 44 and 45.
  • the several pivot-pins 40, 44, and 45 are provided with knife-edge portions which cooperate with angular recesses of greater width in the hearings in the manner already described in order that the toggle-levers may respond readily and quickly to any pressure exerted in the proper direction to move the toggle-joint over beyond the dead-center in the direction necessary to release the circuit-breaker.
  • I pro- Vide a core 40 for the coil 31, (shown clearly in Fig. 6,) the end of which is located near to an armature 47 in the form of a lever, which is pivoted between its ends to a bracket 48 on the casing, projects through an opening 48 in a partition-plate 48 and is connected at its inner end to a rod 49, the latter being pressed outward by means of a coiled spring 50.
  • the rod 49 is screw-threaded, and ad justing and locking nuts 51 are provided in order to set the armature for any maximum current that may be desired.
  • the outer end of the armature-lever 47 is pivoted to one end of an arm or rod 52, the other end of said arm having a pin 53, so located when the circuitbreaker is closed that movement of the arma' ture 47 by reason of excessive current through the coil 31 will cause the pin to engage the toggle-levers and move them a SHfillOlGlll) dis tance to carry the joint beyond the dead-cen- I-61',Wh6[l the spring 33 will complete the movement of the blade 32 to the position shown in broken lines in Fig. 5.
  • knifeedge bearings may be varied in number, as well as in structure and arrangement, from what has been shown and described and that the details of construction may be otherwise modified without departing from the spirit and scope of my invention.
  • An antifriction pivot hearing or joint comprising a part having a cylindrical recess and a part having an angular recess formed by two plane sides and a curved side, and a pivot-pin having a cylindrical portion which occupies said cylindrical recess and a knifeedge portion which occupies said angular recess and has a curved side of less width than that of the recess.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Breakers (AREA)

Description

No. 633,773 Patented Sept. 26, I899.
a. WRIGHT.
CIRCUIT BREAKER.
(Application filed Max. 23, 1899.)
2 Sheets-Sheet WITNESSES @Ww M 6 No. 633,773. Patnted Sept. 26, I899. G. WRIGHT.
CIRCUIT BREAKER.
(Application filed m 23, 1899.) (No Model.) 2 Sheets-Sheet 2.
a 5 3.9 O z W 0 S IN VENTOR A TTURQNE 7'.
m: Now: warms co. wow-urns. WASHINGTON. n. r.
UNITED STATES PATENT OFFIcE.
GILBERT IVRIGHT, OF IVILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE IVESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, OF PENN- SYLVANIA.
CIRCUIT-BREAKER.
SPECIFICATION forming part of Letters Patent No. 633,773, dated September 26, 1899.
Application filed MarohZB, 1899. Serial No. 710,280. (No model.)
T all 107007771 51 WW/j EON 08 7 other substantially infusible conducting ma- Beitknown that I, GILBERT \VRIGHT, a cititerial. The lower main contact-terminal 3 is zenof the United States, residingat Wilkinspartially surrounded by a body of iron 8, burg, in the county of Allegheny and State of there being an air-gap S of any desired width 5 Pennsylvania, have invented a new and useat its upper end in order that the magnetic 55 ful Improvement in Circuit-Breakers, (Case flux maybe diverted at this point through No. 817,) of which the following is a specithe armature 9, which is mounted upon two fication. arms 10, these arms being pivotally mounted My invention relates to that class of devices in brackets 11, which may be parts of a single employed for automatically opening electric casting, the base of which may be suitably 6o circuits when the current therein exceeds a fastened to the panel 1 by means of bolts expredetermined amount, which are generally tending through the part 8. If the circuitknown as circuit-breakers. breaker is to be used in connection with alter- The object of my invention is to provide a natii'lg-current circuits, the parts 8 and 9 circuit-breaker which shall be simple in 0011- should be laminated; but for direct-current structionand effective in operation and which circuits they may form integral parts, remay be more easily and certainly locked in spectively, of the brackets 11 and the arms operative position and released from such 10, if found more convenient or desirable. position when the conditions of the circuit The arms 10 are provided with upwardly- 2o demand it than has been possible in devices projecting lugs or ears 10, having openings 7c of this character heretofore employed. for a pivot-pin 10", beyond which they are In the accompanying drawings, Figurel isa l joined by a transverse bar 12. A single arm side elevation of one form of circuit-breaker l2 projects from the middle of bar 12 and is constructedin accordance with myinvention, provided with a scale 13, a weight It, and
25 and Fig. 2 is a front elevation of the same, with a screw 15 and thumb-nut 16 foradjustthe circuit-breaker being in closed position in ing the weight longitudinally on the arm both figures. Figs. 3, 3, and 3" are perspec- The main movable contact member of the tive views of certain details of the locking circuit-breaker comprises a bundle of curved and releasing mechanism, and Fig. at is a delaminae 17, which are bolted or riveted to a 30 tail view of one of the stationarycontact-tersupporting-arm or pair of arms 18, the ends minals and adjacent parts. Fig. 5 is a botof the laminae 17 being free to be deflected as tom plan view of another form of circuitthey are pressed against the faces of the stabreaker, the cover being removed and parts tionary terminals 2 and 8. being broken away. Fig. 6 is a transverse For the purpose of making tinal contact 5 sectional view of the device shown in Fig. 5. with the upper terminal 2 I provide a small Referring now particularly to Figs. 1 to l plate or block 19 and mount a small contactof the drawings 1 is a non-conducting baseblock 19 upon the upper end of a spring-plate plate or support which will ordinarily be a 20, this plate being securely fastened elecswitchboard-panel of slate, marble, or similar trically and mechanically to the laminated 4o material. The stationary contact-terminals contact 17. The plate 20 is extended down- 0 2 and 3 are mounted upon the face of the baseward below the lower end of the contact memplate 1, and each is provided with a stud at, ber 17 and is of such length and of such form which projects through the base-plate in oras to make contact at all times with the face der to connect with abus-bar (not shown) at of the lower contact-terminal 3. The sup- 45 the rear of the switchboard. In the form porting-arms 18 for the contact 17 are pivothere shown the two main contact-terminals 2 ally mounted at their lower ends upon a rod and 3 are in vertical alinement, and the up- 18, which is supported by the brackets 11 per one of these terminals has an upwardlynear the base, as shown.
I extending arm 5, having a socket or holder 6, A movable contact-block 21, of carbon or 50 in which is mounted a block 7, of carbon or other substantially infusible material, correrco Lil spending to the stationary block 7, is mounted in a socket 22 on the upper ends of a pair of arms 23, which arms are pivotally connected to the upper ends of the arms 18 by a pin 23. The arms 23 are provided with extensions 23", which project downwardly and inwardly beyond their pivotal support and are connected with the supporting-brackets 11 or other stationary portions of the devices by means of coiled springs 2-1-. The operating or closing handle 25 of the circuit-breaker is mounted upon a lever-arm 26, which comprises a sleeve 26 and two arms 20, projecting therefrom inwardly. The sleeve 26 is located between the outer ends of brackets 11, and it is pivotally mounted upon the pin 10. A toggle-lever arm 27 extends between the pivot-pin 23 and a pin 27, located in the free ends of le ver-arms 26 The parts are so adjusted that when the circuit-breaker is closed the joint between the arms 2o and 27 of the togglelever is slightly beyond the dead-center-i. 6., above the line joining the centers of the two pivot- pins 10 and 23 The closing-lever 26 is provided on its under side with a lug 28, that projects toward and within a short distance of the arm 12, so that when the current through the circuit-breaker increases to such an extent as to set up a magnetic flux that pulls upon the armature 9 suflieiently to overcome the pull of weight 14 the arm 12 will strike against the lug 2S, and thus throw the toggle-joint downward below the line connecting the centers of the two pivotpins 10 and 23". The springs 24, acting in conjunction with gravity, will throw the movable members of the circuit breaker outward and downward and away from the stationary contact members. It will be seen that the springs 24, the upper ends ofwhich are attached to the projecting ends 23 of arms 20, will first hold the shunt contact-terminals 21 and 7 in engagement until the contact member 17 has been separated from the stationary terminals 2 and 3, and any current that is not shunted through the contact members 7 and 21 will be broken between the contact-pieces l9 and 19, since the former is supported upon a spring 20, that serves to hold it in engagement with the piece 19 after the contact member 17 has moved away from the cooperating terminal blocks 2 and In order that this circuit-breaker may be easily closed and that it may respond quickly and easily to the action of the tripping mechanism, I provide knife-edge bearings for the toggle- lever arms 26 and 27. The portions of pivot-pin 23 which are located in arms 18 and 23 are cylindrical and are loosely fitted into the said parts. The middle portion of this pivot-pin is partially cut away to form a knife-edge portion 23, and this knife-edge rests in an angularcut-away portion of a bushing 23, the angle between the sides of which is greater than that between the sides of the cooperating knife-edge portion, (see Fig. 3,) so that the two parts may turn with reference to each other without friction until the toggle'joint has passed its dead-center, when there is no longer any danger of binding be tween the parts on account of pressure exerted.
The portions of pivot-pin 27 which are located in the ends of lever-arms 26 are cylindrical, and the middle portion, which is located in the end of lever-arm 27, is partially cut away to form a knife-edge portion 27 This knife-edge portion is located in an angular recess in a bushing 27 the angle between the sides of the recess being greater than that between the sides of the knifeedge portion 27 for the same reason as that stated with reference to the bearing 23. (See Fig. 3.)
The portions of pivot-pin 1O which are located in the ears and in the sleeve 26 are cylindrical in form, and the portions which are located in the brackets 1.1 are partially cut away to form knife-edge portions 10. I provide bushings 10 for the cut-away portions of the pivot-pin 10 each of which is cut away to form an angular recess, the angle between the sides of which is greater than that between the inclined sides of the pertions 10 for the reason stated with reference to bearings 23 and 27. (See Fig. 3.)
Referring now to Figs. 5 and G, the form of circuit-breaker here shown is designed and intended especially for use on railway-vehicles, and the operative parts are therefore inclosed in a casing 1 instead of being mounted upon aswitchboard. The stationary terminal 29, to which main conductor 30 is connected, constitutes one terminal of the actuating-coil 31 of the circuit-breaker. The other terminal 29 of the coil 31 is eleetricallyconnected to the movable member or blade 32 of the circuit-breaker, the latter being pivotally mounted upon the said terminal29. A spring 33, here shown as coiled around the pivotbearing 34 of the blade 32, but which may be of any desired construction, is provided for throwing the movable member or blade outward when it is released. The other main conductor 35 is connected to a terminal block 36, in which is mounted a laminated contact member 37, having a beveled free end and located in a position to be engaged by the edge of the blade 32 or with a suitable block or plate 32, set in the edge of said blade. The terminal block 36 is also provided with two plates 38, which are either of resilient material and somewhat flexible, so as to spring to permit the end of the blade to enter between them, or loosely mounted and pressed toward each other by means of springs of suitable construction, these devices being enr- ITS is mounted upon a pivot 40 and is joined to the movable member 32 of the circuit-breaker bya toggle-lever 41,0ne arm 42 of which is rigid with the handle and the other arm 43 of which comprises two plates or bars spaced apart in order to receive at one end the free end of arm 42 and at the other end blade 32, the connecting means for the respective ends being pivot-pins 44 and 45. The several pivot-pins 40, 44, and 45 are provided with knife-edge portions which cooperate with angular recesses of greater width in the hearings in the manner already described in order that the toggle-levers may respond readily and quickly to any pressure exerted in the proper direction to move the toggle-joint over beyond the dead-center in the direction necessary to release the circuit-breaker.
In order to release the circuit-breaker when the current exceeds the limit of safety, I pro- Vide a core 40 for the coil 31, (shown clearly in Fig. 6,) the end of which is located near to an armature 47 in the form of a lever, which is pivoted between its ends to a bracket 48 on the casing, projects through an opening 48 in a partition-plate 48 and is connected at its inner end to a rod 49, the latter being pressed outward by means of a coiled spring 50. The rod 49 is screw-threaded, and ad justing and locking nuts 51 are provided in order to set the armature for any maximum current that may be desired. The outer end of the armature-lever 47 is pivoted to one end of an arm or rod 52, the other end of said arm having a pin 53, so located when the circuitbreaker is closed that movement of the arma' ture 47 by reason of excessive current through the coil 31 will cause the pin to engage the toggle-levers and move them a SHfillOlGlll) dis tance to carry the joint beyond the dead-cen- I-61',Wh6[l the spring 33 will complete the movement of the blade 32 to the position shown in broken lines in Fig. 5.
It will be readily understood that the knifeedge bearings may be varied in number, as well as in structure and arrangement, from what has been shown and described and that the details of construction may be otherwise modified without departing from the spirit and scope of my invention.
I claim as my invention 1. In an automatic electric circuit-breaker, the combination with the stationary andmovable contact-terminals, of toggle-levers for closing the breaker and constituting the sole means for locking the same, and knife-edge bearings for said levers.
2. In an automatic electric circuit-breaker, the combination with stationary and movable contact-terminals,toggle-levers for closing the breaker and constituting the sole means for locking the same, knife-edge bearings for said toggle-levers and electromagnetically-actw ated means for moving the levers out of look ing position.
3. In an automatic electric circuit-breaker, the combination with stationary and movable contact-terminals, of toggle-levers for sup porting and actuating said movable terminals and knife-edge bearings for said levers, the toggle-levers being so arranged and adjusted that the toggle-joint is movable beyond the dead-center to lock the circuit-breaker in operative position.
4. The combination with two relatively movable devices or parts, of a joint therefor comprising a cylindrical pivot or bearing pin having one or more knife-edge portions, one or more angular recesses in one of said devices or parts occupied by said knife-edge portion or portions, and one or more cylindrical bearings in the other device or part occupied by the cylindrical portion or portions of the pivot orbearing pin.
5. An antifriction pivot hearing or joint comprising a part having a cylindrical recess and a part having an angular recess formed by two plane sides and a curved side, and a pivot-pin having a cylindrical portion which occupies said cylindrical recess and a knifeedge portion which occupies said angular recess and has a curved side of less width than that of the recess.
6. The combination with two relatively movable devices or parts, of a pivot-pin joining said parts and having one or more knifeedge portions and a bushing having one or more angular recesses occupied but not filled by said knife-edge portion or portions.
In testimony whereof I have hereunto subscribed my name this 20th day of March, 1899.
GILBERT IVRIGHT.
lVitnesses:
WESLEY G. CARR, H. C. TENER.
US71023099A 1899-03-23 1899-03-23 Circuit-breaker. Expired - Lifetime US633773A (en)

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