US2733384A

US2733384A - L niebauer

Info

Publication number: US2733384A
Authority: US
Priority date: 1951-10-23
Publication date: 1956-01-31
Anticipated expiration: 1973-01-31
Also published as: FR1080476A

Description

Jan. 31, 1956 K, L. NIEBAUER 2,733,384

AUTOMATIC RECLOSING CIRCUIT BREAKER Filed Oct. 23, 1951 4 Sheets-Sheet l WITNESSES: INVENTOR 5 47 12 Kenneth L.Niebouer. ML 7% ATTORNEY Jan. 31, 1956 K. L. NIEBAUER 2,733,334

AUTOMATIC RECLOSING CIRCUIT BREAKER Filed Oct. 23, 1951 4 Sheets-Sheet 2 Fig.2.

WITNESSES: INVENTOR Kenneth L.Niebouer. J. Um BY ATTORNEY Jan. 31, 1956 K. L. NIEBAUER AUTOMATIC RECLOSING CIRCUIT BREAKER 4 Sheets-Sheet 3 Filed Oct. 23, 1951 Fig.4.

( 23 Insulation INVENTOR Kenneth L.Nieb

WITNESSES: 5%7 7" Jan. 31, 1956 K. L. NIEBAUER AUTOMATIC RECLOSING CIRCUIT BREAKER 4 Sheets-Sheet 4 Filed Oct. 25, 1951 INVENTOR Kenneth L.Niebo WITNESSES: 7v

ATTORNEY United States Patent 2,733,384 AUTOMATIC REfiLOSING cli'zcur'r BREAKER Kenneth L. Nihauer, Wilkiushurg; p sna -nor to westihghouse Electric Corporation; East Pittsburgh, Pa., a corporation of Pennsylvania Application October 23, 1s1, Serial No. 252,648 17 claims. (or. 31142) My invention relates generally to circuit interrupters, and it has reference in particular to circuit interrupters of the automatic reclosing type. Automatic reclosing circuit breakers are generally of the oil-filled type. Since such reclosers are often located and are seldom serviced,

automatic opening and reclosing operations.

It is also another object of my invention to provide in These and other objects of this invention will become more apparent upon consideration of the following detailed description of a preferred embodiment thereof, when taken in connection with the following drawings, in which:

Figure 1 is a front elevational view of a reclosing circuit breaker embodying the invention in one of its forms;

Fig. 2 is an enlarged partly sectioned view of the reclosing circuit breaker of Fig. 1 with the tank and cover casting sectioned along the line 11-41;

v Fig. 3 is an enlarged sectional view of the counter shown in Fig. 2; 4

Fig. 4 is a partly broken out enlarged side elevational view. of the sectionalizing switch shown in Fig. 2; and Fig. 5 isan enlarged sectional view of the interrupter forming part of the recloser of Fig. 1 7 I 1 I Referring to Fig. 1 ofthedrawings, it will be seen that an. automatic reclosingtcircuit breaker 1 0 embodying the principal features of the invention may comprise gener- 2,733,384 Patented Jan. 31, 1956 ally a sectionalizing switch or sectionalizer 11 having an interrupting device 12 mounted on the sectionalizing switch and connected in series circuit relation therewith. Referring to Figs. 2 and 4, it will be seen that the of James M. Wallace et al., and assigned to the assignee coil 19, the circuit continues through a conductor 21 separated from the conductor 18 by insulation 20, back underneath the bushing 17 for the lead 16; and thence to the terminal 22 which constitutes one of the stationary contacts of the sectionalizer. the sectionalizer has two Bushings, each with its lead passing through the bushing, v at its bottom, in

the

stationary contacts

22 and 24 in the closed position of the sectionalizer, and which is lowered by gravity, to operate the se'ctionalizer, upon the release of a pull rod 27, which is" shown in the form of an upwardly extending insulating tube, which has an L-shaped guide plate 28 thelike, is contact bar 26 by a spring 35. p p A counter and lockout mechanism is segregated, in Fig. 2, into its component parts, consisting of the counter 37 and the operating inechanism 38.

The sectionalizer 11 can theoretically operate either in The particular operating-mechanism 38 Which is shown in the accompanying drawings constitutes the subjectmatter of application Serial No. 106,887, now Patent No. 2,697,149, of J. M. Wallace and A. W. Ogg, entitled Operating Mechanisms for Line Sectionalizers and the Like, which was filed on July 26, asslgnee of the present invention. suffice to say that this operating-mechanism comprises a bellcrank trigger 53 and an operating-handle 60. The

the lever 43 which is generally triangular. A lever 46, which is connected in toggle arrangement with the handle is pivotally connected to the third pointof the lever 43. The trigger 53 has a downwardly extending abutment-portion 56 which is adapted to be tripped when an upward movement of a trip-pin 57 of the counter 37 raises tends partly within and said abutment point 56 of the trigger, whereupon the linkage of the operating-mechanism permits the pull rod 27 and the movable-contact member 26 to drop freely in the opening operation of the mechanism.

The counter 37 is suspended from the top of the'top casting 15, by means of the depending insulating supports or tubes 33, which support a magnetizable base plate 59 of the counter.

The counter 37 is shown in detail in Fig. 3, and may be of the type disclosed in the copending application Serial No. 189,082 of James M. Wallace, entitled Circuit interrupter and Counter Therefor, which was filed on October 9, 1950, and is assigned to theassignee of the present invention, and comprises a vertically disposed tube 62, which is preferably made of brass or other non-magnetizable metal. The lower end of thetube is partially closed by a plug 63 of iron which acts as a stationary magnetic core having an orifice controlledby a ball check valve 77 to provide a one way inlet, while the top of the tube 62 is open. The series current the tube 62, intermediate between its upper and lower ends. Immediately above the coil 19 is a magnetizable plate 64 which is perforated so as to surround the tube 62. The plate 64 is magnetically connected by bolts 66 to the base plate 59 so as to secure coil 19 to the base plate, and serve as one of the two pole pieces of an electromagnetic circuit, the excitation of which is provided by the coil 19.

Inside of the tube 62 is a magnetizable core or armature 67, which is slidably movable, with a relatively close fit, for example having about 3 mils radial clearance, within said tube. The armature 67 extends partly above and partly below the level of the upper plate64, while the plug or core 63 extends partly above and partly below the base plate 59. Each of the members 63 and 67 thus expartly without the space between the

plates

64 and 59, respectively.

The armature 67 has a cylindrical extension 63 at its upper end, over which fits slidably a non-magnetic cylindrical cap 69. The cap 69 is provided with a plurality of annular magnetizable ribs or rings 73 which are vertically spaced from each other by a spacing which is preferably approximately the same distance as the closable distance between the core 63 and the armature 67, so that they will, in conjunction with a magnetizable ring 75 about the tube 62, magnetically lock the cap against unwanted vertical displacement or slippage. A compression spring 74 is disposed between the core 63 and armature 67, so that, when the coil 19 is sufliciently energized, the armature is attracted toward the core, storing up energy in the interposed compression spring 74, as will be more fully described hereafter.

The core 63 isprovided with a central bore 7 6, the lower end of which is closable by means of a ball check valve 77 and the armature 67 has a similar bore 7 9 and ball check valve 80, so that the fluid which is entrapped within the closed lower end of the tube 62 can flow up into the extension 68 and cap 69, but resists any rapid downward movement of the cap, because of the closure of these

ball valves

77 and 80, while said valves permit the free upward movement of either armature 67 or cap 69. The entrapped fluid could be any gas or liquid having the required viscosity in comparison with the mechanical clearances which are provided. The idea is to permit the cap 69 to move freely upwardly, in a step by step motion, as will be subsequently described, while permitting the cap to drift back downwardly again, by fluid leakage, at a very slow rate.

At the top of the cap 69 is an upstanding pin 82, which extends upwardly to a point above the open top end of the tube 62. This pin 82 is surrounded by a tubular tip or trip-pin 57, which is capable of actuating the trigger 53 after any desired number of counts, such as 1, 2, 3 or 4, within the range of the countingmechanism 37.

In the operation of the counting mechanism 37, when the coil 19 is first energized, with a current corresponding coil 19 surrounds a portion of to the setting of the counter, the armature 67 is drawn downwardly, so as to close the air gap which separates the inner ends of the core 63 and armature .67. The cap 69 cannot move downwardly, because of the holding effeet of the magnetic rings 73 in the magnetic field at upper plate 64, and hence the armature 67 must move downwardly relative thereto. When the circuit is interrupted, the spring 74 forces the armature 67 upwardly and the cap 69 is carried upwardly therewith. Upon reenergization of the coil 19 the armature 67 is again drawn down relative to the cap 69, and upon subsequent inte1ruption of the circuit the spring 74 again raises the armature 67 and the cap 69 with it, until the next magnetic ring 73 comes into the field of the plate 64. This action continues until the pin 57 engages the trigger 53 to break the toggle mechanism and. drop contact rod 27, thereby separating movable contact 26 from

contacts

22 and 24.

Referring to Fig. 5, it will be seen that the interrupting device 12 may be enclosed in a generally cylindrical casing 102 of insulating material such as porcelain or the like, which is an integral part of the sectionalizer bushing 23, and is open at the top and closed at the bottom, except for a central aperture throughwhich extends the stem 103 of a stationary contact 104 which may be threadably connected with the terminal conductor 25 of the sectionalizer. In general, the interrupting device may be of the explosion type as disclosed in copending application Serial No. 237,502 of Harry I. Lingal et al., entitled Circuit Interrupters, which was filed on July 19, 1951 and is assigned to the assignee of the present invention. As therein disclosed, a movable contact 105 may be mounted on a contact rod 106 slidably disposed for movement relative to the contact 104. An are chamber 197 is provided by a cylindrical cup 108 of insulating material secured to a base plate 109 through which the stem 103 of the fixed contact projects. An orifice 110 lined with a polymer 111, such as polytetrafluoroethylene or the like, surrounds the contact rod 106 where it passes through the cup 168 for assisting in extinguishing an arc drawn during separation of the contacts.

In accordance with the teachings of my invention, a coil 114 may be disposed about a tube 115 which extends between

plates

116 and 117 of magnetic material. The plates are connected by studs 118 also of magnetic material, whch are threaded into

insulating spacers

119 and 120. The spacers 120 are secured to the base plate 109 at the bottom of the casing by screws 124, while the spacers 119 are connected at their upper ends by similar screws to a top plate 126. A flanged cover 127 seals the open end of the casing, being secured to the casing by soldering or other such means. The lower end of the bushing 23 may likewise be provided with a cover solder sealed to the bushing so as to provide a gas tight enclosure which is filled with an arc extinguishing gas such as sulfur hexafluoride or the like, preferably under a pressure of one or more atmospheres. A terminal 128 is secured to the cover by a stud 129 mounted on the top plate 126 and projecting through the cover. A gasket 130 of compressible material such as rubber, co k or the like is interposed between the terminal 128 and cover 127.

The contact rod 106 extends through the tube 115 and is pivotally connected to a lever 131 by a pivot 132 which rides in a slot 133 in the lever. Lever 131 is pivotally mounted on the top of plate 116 by a pivot 135 in supports 136. A channel shaped link 13% is pivotally connected at one end by a pivot to an extension of lever 131, so that the back of the channel lies over the top of the lever. Two springs 142 (only one being shown) are connected to the other end of the link 138 (one to each side thereof), and to a support 144 depending from the top plate 126, so as to provide a predetermined contact pressure between

contacts

104 and 105. The springs 142 are so disposed that they furnish only a contact closing force, and do not function to separate the contacts;

A cylindrical armature 145 is slidably mounted on the contact rod 106 for engaging a collar 146 thereon in response "to a current through the coil 114 in excess of a predetermined value, to separate the contacts. A spring 147 disposed on the rod between the armature and collar, and recessed therein, provides a follow up force foref- A conductor 148 connects the terminal 128 to one end of the coil, while a conductor 149 completes a circuit from the other end of the coil to the moving contact 105. From there the circuit may be traced through the sect iohalizer as hereinbefore described.

In operation, the armature 145 will be actuated in response to a current through the coil 114, and will strike the collar 146, separating the contacts 104 and 165. Lever 131 "rotates clockwise under the influence of th'e armature 145 pushing on collar 146 until its engages the back of channel 138 in Which position the springs 142 no longer exert a downward force on contact rod 106 and the spring 147 can snap the contacts to the full open position. the contacts, an arc is through. The polytetrafluoroethylene liner 111 in the orifice 110 assists in interrupting the are as does also the sulfur hexafluoride gas in the casing 102, as is explained in detail in the hereinbefore referred to copending application of Harry J. Lingal ct al., Serial No. 237,502, filed on July 19, 1951, and assigned to the assignee; of the present invention. After a circuit interrupting operation, the springs 142 act with increasing force to close the contacts 105104 as the lever 131 rotates counterclockwise and the contacts will be closed with a snap action.

When there is a fault on the distribution line, within the protective reach of the interrupter 12 associated with the sectionalizer 11,

interrupter contacts

104 and 105 quickly open, and quickly again reclose as hereinbefore described, but during the time (12 cycles or more, in a 60-cycle line) when said interrupter contacts are open, the sectionalizer-coil 19 is denergized, and the compression-spring 74 between the core 63 and armature 67, which was compressed in response to the fault current, eitpands, and'p'ushes the armature and core apart again, to their normal separation distance. During this action, however, the armature 67 cannot move upwardly relative to cap 69, because of its fluid flow valve 80, and hence the cap must move upwardly with the armature, which it is free to do, so far as fluid action is concerned. The magnetic attraction between the upper plate 64 and the corresponding magnetiiable ribs 73 of the armature 67 is now practically non-existent, because of the deenergization of the coil 19, and hence the armature 67 and cap 69 are notched upwardly by a distance corresponding to the amount of compression of the spring 74.

If a fault continues on the distribution system, at a point beyond the sectionalizer coil 19, the reclosure of the interrupter contacts 104-105 reenergizes the sectionalizer coil 19 and causes a second compression of the spring 74, in a manner already described; If the fault is still on the system, as has just been assumed, the interiiiptei' contacts 104 105 again open, and a second upward stepping movement of the trip pin 57 is obtained. And thus the step by step movement of the counter mechanisni continues.

When the last upward stepping of the armature 67 is obtained, depending upon the vertical positioning of the trip pin or tubular tip 57, this pin 57 comes into contact with the trigger 53 duringlthislast upward movement, and trips out the s'ectionalize'r contacts 262 g It will be noted that this last upward movement of the trip pin to a'c'urr ent in excess 57 occurs during a time when the current in the sectiona'lizer coil 19 is off. In the operation of the interrupter, the current remains off; that is, the interrupter contact remains open; for a minimum of about 12 cycles (on a 60-cycle line), before the interrupter contacts 104105 reclbse. The opening of the sectionalizer contact 26 re- Since certain changes may be made in the above described construction, and different embodiments of the invention may be made without departing from the scope and spirit thereof, it is intended that all the matter contained in the above description and shown in the accompahying drawings, shall be considered as illustrative only and not in a limiting sense.

I claim as my invention:

1. An automatic reclosing circuit breaker comprising, a circuit interrupting device having separable contacts and electroresponsive means operable during an off-current I, of a predetermined value, said sep} arable contacts thereby limiting the number of operations of the interrupter.

5. A unitary circuit interrupter comprising, a container, separable contacts in said container, counting means in said container operable to effect separation of said contacts after a predetermined number of circuit interruptions, insulating means having a sealed chamber filled with sulphur hexafiuoride gas carried by said container, and conducting means in said insulating means providing an electrical connection to said contacts including separable contacts and operating mechanism therefor completely disposed in the sealed chamber and electroresponsive means operable to actuate said mechanism to repeatedly effect separation thereof in response to a current in excess of a predetermined value.

6. A circuit interrupter comprising, a container, a cover for said container, separable contacts supported by said cover in said container, electroresponsive means operable in response to a predeter ined number of circuit interruptions to effect separation of said contacts during a circuit interruption, and means providing an electrical connection to said contacts including a circuit interrupter supported by said cover having separable contact means connected in series circuit relation with the aforesaid contacts and electroresponsive means operable to separate said contacts in response to a current above a predetermined value to continuously effect repeated interruptions of said current.

7. In an automatic reclosing circuit breaker, a sectionalizing switch having a casing with separable contacts therein operated during a circuit interruption by counting means operable in response to circuit interruptions; an insuiator providing an insulated entrance to said casing and interrupting means in said insulator including separable contact means connected in series circuit relation with the aforesaid contacts, said insulator providing a gas tight container for said contact means containing an arc extinguishing gas, and electroresponsive means in the insulator for continuously effecting repeated separations of said contact means in response to a current in excess of a predetermined value.

8. An automatic reclosing circuit breaker comprising, a casing having a metal cover, separable contacts in said casing, an operating mechanism for moving one of said contacts relative to the other, releasable means for normally maintaining said mechanism in a position for maintaining said contacts engaged, electroresponsive means in said casing operable after a predetermined number of circuit interruptions and during an interruption to effect release of said releasable means, an insulating bushing mounted on said cover, separable contact means in said bushing, means connecting said contact means in series circuit relation with said separable contacts including electroresponsive means having a coil connected in series with said contact means for repeatedly separating them in response to a current in excess of a predetermined value, said bushing providing a solder-sealed container maintaining said contact means in an atmosphere of sulfur hexafluoride.

9. A circuit interrupter comprising, separable contacts, an operating mechanism operable to separate or close said contacts, counting means operable in response to a predetermined number of interruptions of a current in excess of a predetermined value to effect separation of said contacts during a circuit interruption, an enclosure for said contacts, operating mechanism and counting means, a solder-sealed container filled with an are extinguishing gas supportedby and providing an insulated entrance into said enclosure, separable contact means dis posed in said container connected in series with said counting means and separable contacts, and eiectroresponsive means connected in series with the separable contact means operable in response to a current in excess of a predetermined value to repeatedly eiiect separation of said contact means to interrupt the circuit.

10. In a circuit interrupter, a container, a cover for said container, separable contacts biased to separate and supported by said cover in said container, a lever connected at one point to one of said contacts, toggle means providing a pivotal support for the lever at another point, releasable means pivotally supported from the cover to provide a pivotal support for the lever at a point spaced from said other points to maintain the contacts closed, electroresponsive means supported from said cover in said container operable in response to a predetermined number of circuit interruptions to effect release of said releasable means while the circuit is interrupted, a separate solder-sealed container supported by said cover, separable contact means disposed in said separate container and connected in series with said eleetroresponsive means, and electroresponsive means in said separate container for separating said contact means including an armature movable in response to a current in excess of a predetermined value to repeatedly efiect separation of said contact means until the separable contacts are separated.

11. An automatic reclosing circuit breaker comprising, a sectionalizing switch having separable contacts normally closed and opened during an interruption of the circuit by counting means after a predetermined number of circuit interruptions, and an interrupter disposed in a sealed insulating bushing filled with sulfur hexafiuoride'gas comprising separable contacts and mechanism therefor com pletely disposed in an arc extinguishing medium and having electroresponsive means continuously operable to repeatedly separate them in response to a current in excess of a predetermined value.

12. In an automatic reclosing circuit breaker the combination, of a casing, a sectionalizing switch in said casing having terminals connected by separable contacts and counting means responsive to a predetermined number of circuit interruptions for effecting separation of said contacts, and means providing an insulated connection into said casing including an insulating bushing mounted on said casing and having separable contact means therein biased to close and connected in series with said separable contacts, counting means and terminals, and electroresponsive operating means continuously operable to repeatedly separate said contact means in response to a current in excess of a predetermined value.

13. An automatic reclosing circuit breaker comprising, a casing, a sectionalizing switch in said casing having terminals connected by separable contacts and counting means operable in response to a predetermined number of circuit interruptions to effect. separation of said contacts; and means providing an insulated connection to said terminals including an insulating bushing mounted on said casing having a circuit interrupter therein with separable contact means connected in series with said terminals and sectionalizing switch, electroresponsive means operable in response to a current in excess of a predetermined value continuously operable to repeatedly separate said contact means, said bushing providing a sealed enclosure maintaining said contact means in an atmosphere of sulfur hexafiuoride gas.

14. An automatic reclosing circuit breaker comprising, a container, a cover for said container, terminal'conductors, insulating means providing for passage of said terminalconductors through the cover including an insulating bushing having a gas tight chamber therein, stationary contacts supported by said terminal conductors in said container, a movable contact, an operating mechanism supporting said movable contact for movement relative to said stationary contacts, releasable means for maintaining said operating mechanism in a position with the movable contact engaging the stationary contacts, counting means operable in response to a predetermined number of circuit interruptions to actuate said releasable means to effect separation of said contacts, separable contacts disposed in said chamber in series with the aforesaid contacts including a fixed contact connected to said terminal and a movable contact, operating means for said movable contact completely disposed within said cham- Let, eiectroresponsive means mounted in said bushing to act .ate said means for operating the movable contact to repeatedly separate it from the stationary contact an indefinite number of times in response to a current in excess of a predetermied value, said movable contact being biased to reengage the fixed contact following such eparation, and a cover for said bushing carrying a terminal connected in circuit with the electroresponsive means and movable contact.

15. A circuit interrupting device comprising, first set of separable contacts, overload responsive means operable to effect separation of said contacts, said contacts being biased to reclose following every separation, a second overload responsive means operable to count closely successive occurrences of overload on the circuit, and a second set of separable contacts connected in series with said first set disposed to be separated by said second overload responsive means and maintained separated only after a predetermined number of separations of said first set of contacts to limit the number of operations of said first set of separable contacts.

16. In a circuit interrupter, a pair of terminals, a first set of separable contacts connected between said erminals, overload responsive means operable to separate said contacts, said contacts being biased to reclose following every separation, a second overload responsive means operable to count closely successive separations of said contacts, and a second set of separable contacts connected between said terminals in series circuit relation with said first set of contacts disposed to be separated by said second overload responsive means during separation of said first set and maintained separated only after said second overload responsive means has counted a predetermined number 10 of closely successive separations of said first set of separable contacts.

17. A circuit interrupting device comprising, a first set of separable contacts, overload responsive means operable to effect an indefinite number of repeated separations of said contacts, said contacts being biased to reclose following each separation, counting means advanced in response to closely successive separations of said first contacts, a second set of contacts connected in series with said first set separable only after a predetermined count by said second overload responsive means, a container for said second set of contacts and said second overload responsive means, and means providing electrical connections to said second contacts and overload means including a hollow insulating bushing for said container disposed to completely contain said first set of contacts and said first overload responsive means.

References Cited in the file of this patent UNITED STATES PATENTS 1,925,861 Baum Sept. 5, 1933 1,982,986 Garlington Dec. 4, 1934 2,142,188 Gaston Jan. 3, 1939 2,337,713 Garlington Dec. 28, 1943 2,349,632 May May 23, 1944 2,361,221 Ludwig Oct. 24, 1944 2,387,372 Watkins et a1 Oct. 23, 1945 2,457,939 Straup Ian. 4, 1949 2,464,303 Gesellschap Mar. 15, 1949 2,487,025 Matthews Nov. 1, 1949 2,563,136 Schindler Aug. 7, 1951