US1138754A - Circuit-interrupter. - Google Patents

Circuit-interrupter. Download PDF

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Publication number
US1138754A
US1138754A US58385910A US1910583859A US1138754A US 1138754 A US1138754 A US 1138754A US 58385910 A US58385910 A US 58385910A US 1910583859 A US1910583859 A US 1910583859A US 1138754 A US1138754 A US 1138754A
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Prior art keywords
shaft
circuit
spring
crank
disk
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US58385910A
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Ford W Harris
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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
    • H01H71/00Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
    • H01H71/10Operating or release mechanisms
    • H01H71/12Automatic release mechanisms with or without manual release
    • H01H71/24Electromagnetic mechanisms
    • H01H71/2454Electromagnetic mechanisms characterised by the magnetic circuit or active magnetic elements

Definitions

  • My invention relates to tripping devices, 7
  • the object of my invention is to provide a device, of the above-indicated class, that shall be simple and durable in construction and effective and reliable in operation.
  • I provide an auxiliary actuatin device which depends for its action upon he device may be set by hand and be locked in its set position by means of a small latch .which is adapted to be disengaged by a suitable tripping magnet.
  • a plurality of interrupter-s may be so interconnected that the actuating device furnishes sufiicient power to trip them all, under predetermined circuit conditions.
  • a plurality of such devices may be connected to a single interconnecting mechanism and each device may be rendered responsive to predetermined conditions of a separate circuit, so that reliable concurrent action of a plurality of circuit interrupters may be secured, under predetermined conditions of a plurality of separate circuits.
  • Figure 1 is a view, partially in side elevation and partially in vertical section, of an auxiliary trippmg device constructed in accordance wlth my invention.
  • Fig. 2 1s a diagrammatic view of a plurality of circuit interrupters having the tripping device and interconnecting mechanlsm wh1ch constltute my 1I1VeI1' tion.
  • Figs. 3 and 4 are, respectively, a rear and front face view of the tripping device shown in Fig. 1, and Fig. 5 is a rear View of a portion ofsaid device.'
  • a supply -circuit 12- delivers energy to a distribution circuit 31 through feeder conductors 5 and 6 and a plurality of circuit interrupters 7 and 8, said circuit interrupters being Specification of Letters Patent.
  • the clrcuit interrupters 7 and 8 are of like construction and each comprises stationary contact terminals 11, movable bridging contact terminals 12, and operating mechanism 13 and a tripping mechanism 14.
  • the tripping mechanism 14 includes an overload electromagnet .15, having a movable armature 16 which is pivotally supported on a pin 17 and, under predetermined conditions, is adapted to engage an arm 18 of a bell crank lever 19- which is also pivoted upon the pin 17
  • the operating mechanism 13 of each interrupter is held in its set position by means of a pivotally supported latch member 20, which is adapted to be released by the arm 18 of the bell crank lever 19, as will be hereinafter described.
  • the bell crank levers 19 have downwardlyprojecting arms 21 the lower ends of which are pivotally secured to a common connecting member 22, said member being also connected to the auxiliary tripping device 9.
  • the structural details of circuit interrupters 7 and 8 may, of course, be varied considerably, or any other suitable devices for accomplishing the same purposes may be employed in their stead.
  • the tripping device 9 comprises an insulatingpanel or slab 25, upon one side of which an electromagnet 26, of a common type of construction, is mounted.
  • the movable core 27 of the electromagnet 26 is provided at its upper end with a rod 28 having a plurality of adjustable weights 29, and, at its lower end, with a. rod 30 having adjustable lock nuts 31.
  • the lock nuts 31 are adapted to engage an outer laterally projecting integral part 32 of a U-shaped latch member 33 which is pivotally mounted upon a pin 34.
  • the inner portion of the latch member 33 is provided with a laterally projecting pawl 35 'which normally engages one of a plurality of notches 36 in the periphery of a disk 37
  • a spring 38 surrounds the pin 40 in the panel 25 and is held in position by means of face plates 41 and 42 which are mounted upon the respective sides of said panel.
  • a heavy coil-spring 43 surrounds the shaft 39 within the opening 40, and the ends of said spring are respectively secured to the disk 37 and to the face plate 41.
  • Adjacent to the face plate 41 is a disk member 45 which is fastened to the shaft 39 and is provided, at diametrically opposite points, with lateral-projections 46 and 47 for a purpose to be hereinafter specified.
  • a lever member 48 Adjacent to the face plate 41 is a disk member 45 which is fastened to the shaft 39 and is provided, at diametrically opposite points, with lateral-projections 46 and 47 for a purpose to be hereinafter specified.
  • havin lateral projections 49 and 50 which are a apted to be engaged by the projections 46 and 47 respectively, when the spring 43 is released, is loosely mounted upon the shaft 39 and is free to rotate in either direction.
  • the lever member 48 is provided with a downwardly extending arm 51, the lower end of which is pivotally connected to the connecting member 22.
  • a suitable insulating hand wheel 52 is fastened to the outer nd of rod 39.
  • the tripping device of my invention is adapted for no-voltage operation, and the movable core 27 is adapted to release the power spring 43 when the electro-magnet 26 is denergized, as will be readily understood.
  • the movable core 27 is adapted to release the power spring 43 when the electro-magnet 26 is denergized, as will be readily understood.
  • said device may be readily adapted for overload operation by mounting the latch member 33 and spring 38 upon a pin 53, as shown in Fig. 5 and adjusting the lock nuts 31 to engage the under side of the arm 32 when the magnet is energized a predetermined amount.
  • the operation of the tripping device is as follows: Upon the occurrence of a no-voltage condition upon the supply circuit 12, to which the winding of electro-magnet 26 is connected, said electro-magnet is deenergized and the movable core 27 is allowed to drop. Such action causes the lock nuts 31 to engage the arm 32 of latch member 33 and, consequently, forces the pawl 35 out of its notch 36in the disk 37. The coil-spring 43, is thereby released and causes the shaft 39 to be suddenly rotated in a clockwise direction,
  • the handle 52 is turned by counter-clockwise rotation and torsional potential energy
  • one of the magnets 15 is sufficiently energized to cause its movable armature 16 to deliver a sudden blow to the arm 18 of the bell crank lever member 19, and, by reason of the impact of said movable armature upon the bell crank lever member, the comparatively light interconnecting mechanism is actuated to cause the release of all the latches 20 and, therefore,'a simultaneous opening of all the interrupters is effected.
  • the lever member 48 is loosely mounted upon shaft 39, it is evident that no restraint is imposed upon the action of said interconnecting mechanism, by the auxiliary tripping device.
  • auxiliary tripping device associated with the connecting member 22
  • each device may be rendered electro-responsive to predetermined circuit conditions of individual circuits, so that simultaneous opening of a plurality of interrupters may be accomplished in response to a predetermined circuit condition of any one of a plurality of separate circuits.
  • a tripping device comprising a supporting member, a rotatable shaft, aresilient member disposed between said shaft and said supporting member, means for restraining said resilient member, and electro-responsive means for releasing said restraining means under predetermined conditions, a crank, and a lost-motion connection between said shaft and said crank.
  • a tripping device the combination with a circuit interrupter, means for latching the same in a closed position, and a crank to release the latching means, of a shaft on which the crank is mounted, a spring adapted to be tensioned when said shaft is rotated under predetermined conditions, means for restraining said spring, means for releasing said restraining means, and a lost-motion connection between said shaft and said crank.
  • a tripping device for a circuit interrupter comprising a crank for tripping said circuit interrupter, a rotatable shaft, a lostmotion connection between said crank and said shaft, means for operating said shaft, means for restraining said operating means,
  • a tripping device for a circuit interrupter comprising a tripping crank, a supporting means, a rotatable shaft supported by said supporting means, a spring.
  • a tripping device for a circuit interrupter comprising a supporting means, a rotatable shaft supported by saidsupporting means, asprin attached'to said shaft and to said supporting means, means for restraining the saidspring, a disk fastened to said shaft andhaving diametrically opposite lateral projections, and a crank member loosely mounted upon the'shaft and provided with projections adapted to be engaged by the projections of the disk when the spring 1s released.
  • a tripping device comprising a supporting means, ,a rotatable shaft supported -by said supporting means, a ratchet disk and a hand wheel attached to opposite ends ofthe shaft, a spring-attached at' one end to said shaft and at its other end to said supporting means, a pawl adapted to engage said ratchet disk to restrain said spring,
  • said latch under predetermined cona tripping magnet mounted on the panel and adapted to release the pawl, under predetermined conditions, a disk fastened to said shaft and having diametrically opposite lateral projections, and a lever member loosely mounted upon the shaft and provided withprojections adapted to be engaged by the projections of the disk when the spring is released.
  • a switch in the circuit to be controlled means to hold the same inclosed position, a crank to release the switch, a lost motion connection between the crank and the means forholding said switch in closed position, a shaft on which the crank is mounted, a lever and crank to operate the shaft, a spring to actuate the lever, means to normally hold the'leverin inoperative position, a vertically slidable weight adapted to release the lever, and an electromagnet energized by the controlling circuit and adapted to hold I the weight under normal conditions and to dro the weight when the controlling circuit to tile magnet is'broken,
  • a circuit controller the combination of a switch for the circuit to be controlled, a hook to engage the same and hold it closed, a shaft and crank to disengage the hook, a lost motion connection between the crank and hook, a spring, lever and'crank to actuate the shaft, a hook to engage the lever to hold the parts inoperative, a slidable weight adapted to release the hook, and an electromagnet in the controlling circuit adapted to normally hold the Weight elevated and inoperative above the hook. 11.
  • the combination of a switch for the circuit to be controlled adapted to open when released, a hook to engage-the. switch to hold it closed,

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

Description

F. W. HARRIS;
CIRCUIT INTERRUPTER.
APPLICATION man SEPL2 1910.
Patented May 11, 1915.
2 SHEETS-SHEET I.
Ijiyl].
WITNESSES:
and |2VENTQR 2/% 7 AT'TO'RNEY- F. W. HARRIS.
CIRCUIT INTERRUPTER.
APPLICATION FILED SEPT.26, 1910.
Patented May 11, 1915.
-2 SHEETS -SHEET 2- ATTORNEY UNITED STATES PATENT OFFICE.
FORD W. HARRIS, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.
CIRCUIT-INTERRIIPTER.
Application filed September 26, 1910.
My invention relates to tripping devices, 7
and it has special reference to such devices as are adapted for use'with circuit interrupters in order to secure simultaneous action of a plurality of interrupters under predetermined circuit conditions.
The object of my invention is to provide a device, of the above-indicated class, that shall be simple and durable in construction and effective and reliable in operation.
According to my invention, I provide an auxiliary actuatin device which depends for its action upon he device may be set by hand and be locked in its set position by means of a small latch .which is adapted to be disengaged by a suitable tripping magnet. A plurality of interrupter-s may be so interconnected that the actuating device furnishes sufiicient power to trip them all, under predetermined circuit conditions. Furthermore, a plurality of such devices may be connected to a single interconnecting mechanism and each device may be rendered responsive to predetermined conditions of a separate circuit, so that reliable concurrent action of a plurality of circuit interrupters may be secured, under predetermined conditions of a plurality of separate circuits.
In the accompanying drawings, Figure 1 is a view, partially in side elevation and partially in vertical section, of an auxiliary trippmg device constructed in accordance wlth my invention. Fig. 2 1s a diagrammatic view of a plurality of circuit interrupters having the tripping device and interconnecting mechanlsm wh1ch constltute my 1I1VeI1' tion. Figs. 3 and 4 are, respectively, a rear and front face view of the tripping device shown in Fig. 1, and Fig. 5 is a rear View of a portion ofsaid device.'
Referring to'Figs. 1, 2, 3 and 4, a supply -circuit 12- delivers energy to a distribution circuit 31 through feeder conductors 5 and 6 and a plurality of circuit interrupters 7 and 8, said circuit interrupters being Specification of Letters Patent.
avy steel springs. This Patented May 11, 1915.
Serial No. 583,859.
provided with an auxiliary tripping device 9 and an interconnecting mechanism 10.
The clrcuit interrupters 7 and 8 are of like construction and each comprises stationary contact terminals 11, movable bridging contact terminals 12, and operating mechanism 13 and a tripping mechanism 14. The tripping mechanism 14 includes an overload electromagnet .15, having a movable armature 16 which is pivotally supported on a pin 17 and, under predetermined conditions, is adapted to engage an arm 18 of a bell crank lever 19- which is also pivoted upon the pin 17 The operating mechanism 13 of each interrupter is held in its set position by means of a pivotally supported latch member 20, which is adapted to be released by the arm 18 of the bell crank lever 19, as will be hereinafter described. The bell crank levers 19 have downwardlyprojecting arms 21 the lower ends of which are pivotally secured to a common connecting member 22, said member being also connected to the auxiliary tripping device 9. The structural details of circuit interrupters 7 and 8 may, of course, be varied considerably, or any other suitable devices for accomplishing the same purposes may be employed in their stead.
The tripping device 9 comprises an insulatingpanel or slab 25, upon one side of which an electromagnet 26, of a common type of construction, is mounted. The movable core 27 of the electromagnet 26 is provided at its upper end with a rod 28 having a plurality of adjustable weights 29, and, at its lower end, with a. rod 30 having adjustable lock nuts 31. The lock nuts 31 are adapted to engage an outer laterally projecting integral part 32 of a U-shaped latch member 33 which is pivotally mounted upon a pin 34. The inner portion of the latch member 33 is provided with a laterally projecting pawl 35 'which normally engages one of a plurality of notches 36 in the periphery of a disk 37 A spring 38 surrounds the pin 40 in the panel 25 and is held in position by means of face plates 41 and 42 which are mounted upon the respective sides of said panel. A heavy coil-spring 43 surrounds the shaft 39 within the opening 40, and the ends of said spring are respectively secured to the disk 37 and to the face plate 41. Adjacent to the face plate 41 is a disk member 45 which is fastened to the shaft 39 and is provided, at diametrically opposite points, with lateral- projections 46 and 47 for a purpose to be hereinafter specified. A lever member 48,
havin lateral projections 49 and 50, which are a apted to be engaged by the projections 46 and 47 respectively, when the spring 43 is released, is loosely mounted upon the shaft 39 and is free to rotate in either direction. The lever member 48 is provided with a downwardly extending arm 51, the lower end of which is pivotally connected to the connecting member 22. A suitable insulating hand wheel 52 is fastened to the outer nd of rod 39.
As shown in Figs. 1, 2, 3 and 4, the tripping device of my invention is adapted for no-voltage operation, and the movable core 27 is adapted to release the power spring 43 when the electro-magnet 26 is denergized, as will be readily understood. However,
said device may be readily adapted for overload operation by mounting the latch member 33 and spring 38 upon a pin 53, as shown in Fig. 5 and adjusting the lock nuts 31 to engage the under side of the arm 32 when the magnet is energized a predetermined amount.
Assuming the circuit connections and the positions of the various pieces of apparatus to be as shown in Figs. 1, 2, 3 and 4,,the operation of the tripping device is as follows: Upon the occurrence of a no-voltage condition upon the supply circuit 12, to which the winding of electro-magnet 26 is connected, said electro-magnet is deenergized and the movable core 27 is allowed to drop. Such action causes the lock nuts 31 to engage the arm 32 of latch member 33 and, consequently, forces the pawl 35 out of its notch 36in the disk 37. The coil-spring 43, is thereby released and causes the shaft 39 to be suddenly rotated in a clockwise direction,
as viewed from the front of the panel. Thus,
the projections 46 and 47 of the disk member '45 are suddenly projected against the cooperating projections 50 and 49 of the lever member 48 to cause the arm 51 and the connecting member 22 to be actuated suddenly to the left. It is evident that, since the arms 21 of all of the bell crank lever members 19 are connected to the connecting member 22, the latch members 20 of the interrupters 7 and 8 are tripped and thus concurrent action of said interrupters is insured.
In order to re-set the tripping device 9', the handle 52 is turned by counter-clockwise rotation and torsional potential energy,
is stored in the coil-spring 43, as will be readily understood. By reason of the spring 38, the pawl 35 is maintained in engagement with the disk 37 to retain the tripping device in the set position, until again released, through the action of the electromagnet 26.
In case an abnormal current condition exists upon the circuit, one of the magnets 15 is sufficiently energized to cause its movable armature 16 to deliver a sudden blow to the arm 18 of the bell crank lever member 19, and, by reason of the impact of said movable armature upon the bell crank lever member, the comparatively light interconnecting mechanism is actuated to cause the release of all the latches 20 and, therefore,'a simultaneous opening of all the interrupters is effected. Moreover, since the lever member 48 is loosely mounted upon shaft 39, it is evident that no restraint is imposed upon the action of said interconnecting mechanism, by the auxiliary tripping device.
' Although I have shown. but a single auxiliary tripping device associated with the connecting member 22, it will be understood by those skilled in the art that a plurality of such devices may be so connected, and each device may be rendered electro-responsive to predetermined circuit conditions of individual circuits, so that simultaneous opening of a plurality of interrupters may be accomplished in response to a predetermined circuit condition of any one of a plurality of separate circuits.
' Many modifications of the structural details and the arrangement and location of parts may be effected within the scope of my invention and I desire that only such limitations shall be imposed as are indicated in the appended claims.
I claim as my invention:
1. A tripping device comprising a supporting member, a rotatable shaft, aresilient member disposed between said shaft and said supporting member, means for restraining said resilient member, and electro-responsive means for releasing said restraining means under predetermined conditions, a crank, and a lost-motion connection between said shaft and said crank.
2. In a tripping device, the combination with a circuit interrupter, means for latching the same in a closed position, and a crank to release the latching means, of a shaft on which the crank is mounted, a spring adapted to be tensioned when said shaft is rotated under predetermined conditions, means for restraining said spring, means for releasing said restraining means, and a lost-motion connection between said shaft and said crank.
3. A tripping device for a circuit interrupter comprising a crank for tripping said circuit interrupter, a rotatable shaft, a lostmotion connection between said crank and said shaft, means for operating said shaft, means for restraining said operating means,
maepaev sha'ft, means for connecting said crank to said shaft, a spring adapted to be tensloned when said shaft is rotated under predetermined conditions, a latch for restraining said spring, and an electromagnet for. re-' leasing ditions. 5. A tripping device for a circuit interrupter comprising a tripping crank, a supporting means, a rotatable shaft supported by said supporting means, a spring. at-
tachedto said shaft and to said supporting means and adapted to be tensioned when said shaft is rotated under predetermined conditions, a -latch for restraining said spring, and an electro-responsive :means for releasing said latch under predetermined conditions.-
6. A tripping device for a circuit interrupter comprising a supporting means, a rotatable shaft supported by saidsupporting means, asprin attached'to said shaft and to said supporting means, means for restraining the saidspring, a disk fastened to said shaft andhaving diametrically opposite lateral projections, and a crank member loosely mounted upon the'shaft and provided with projections adapted to be engaged by the projections of the disk when the spring 1s released.
7. A tripping device comprising a supporting means, ,a rotatable shaft supported -by said supporting means, a ratchet disk and a hand wheel attached to opposite ends ofthe shaft, a spring-attached at' one end to said shaft and at its other end to said supporting means, a pawl adapted to engage said ratchet disk to restrain said spring,
means for releasing said pawl, a disk fastened to said shaft and having diametrically opposite lateral projections, and a crank member loosely mounted. upon the shaft and provided with projections adapted to be,
engaged by the projections of the disk when the spring is released.
,8. A tripping device-comprising an insulating panel, a rotatable shaft extending through and mounted in face plates on the respective sides of the panel, a ratchet disk and a hand wheel fixed to opposite ends of the shaft, a heavy coil-spring disposed about the shaft and fixed at its ends respectively to the ratchet disk and to one of the face plates, a pawl adapted to restrain the spring,
said latch under predetermined cona tripping magnet mounted on the panel and adapted to release the pawl, under predetermined conditions, a disk fastened to said shaft and having diametrically opposite lateral projections, and a lever member loosely mounted upon the shaft and provided withprojections adapted to be engaged by the projections of the disk when the spring is released.
9. In a circuit controller, the combination of a switch in the circuit to be controlled, means to hold the same inclosed position, a crank to release the switch, a lost motion connection between the crank and the means forholding said switch in closed position, a shaft on which the crank is mounted, a lever and crank to operate the shaft, a spring to actuate the lever, means to normally hold the'leverin inoperative position, a vertically slidable weight adapted to release the lever, and an electromagnet energized by the controlling circuit and adapted to hold I the weight under normal conditions and to dro the weight when the controlling circuit to tile magnet is'broken,
10. In a circuit controller, the combination of a switch for the circuit to be controlled, a hook to engage the same and hold it closed, a shaft and crank to disengage the hook, a lost motion connection between the crank and hook, a spring, lever and'crank to actuate the shaft, a hook to engage the lever to hold the parts inoperative, a slidable weight adapted to release the hook, and an electromagnet in the controlling circuit adapted to normally hold the Weight elevated and inoperative above the hook. 11. In a circuit controller, the combination of a switch for the circuit to be controlled, adapted to open when released, a hook to engage-the. switch to hold it closed,
a shaft, a crank mounted thereon, an electro- FORD W. HARRIS.
Witnesses WILSON L. WRIGHT, B. B. Hmns.
US58385910A 1910-09-26 1910-09-26 Circuit-interrupter. Expired - Lifetime US1138754A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2631190A (en) * 1950-04-17 1953-03-10 Pacific Electric Mfg Corp Circuit breaker latch mechanism

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2631190A (en) * 1950-04-17 1953-03-10 Pacific Electric Mfg Corp Circuit breaker latch mechanism

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