US3150287A - Automatic reclosers - Google Patents

Description

Sept. 22, 1964 M. s. BALDWIN 3,150,287

AUTOMATIC RECLOSERS Filed Feb. 16. 1961 4 Sheets-Sheet 1 IO N INVENTOR Miles S. Baldwin fay/40.9 $1221 ATTORNEY Sept. 22, 1964 M. s. BALDWIN 3,150,287

AUTOMATIC RECLOSERS Filed Feb. 16. 1961 4 Sheets-Sheet 2 Sept. 22, 1964 M. s. BALDWIN AUTOMATIC RECLOSERS 4 Sheets-Sheet 3 Filed Feb. 16. 1961 Sept. 22, 1964 M. s. BALDWIN AUTOMATIC RECLOSERS 4 Sheets-$heet 4 Filed Feb. 16. 1961 FIG.5.

United States Patent 3,150,285 AUTUMATW FEQLQEiERS Mites S, Baldwin, Parana, (Ethic, assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa, 2 corporation of iennsyivania Filed Feb. 16, 196i, Ser. No. 89,823 l 7 Ciairns. (Ci. 317-22) This invention relates to automatic reclosing circuit breakers, and especially to the integrating mechanism and integrating reset mechanism therefor.

This is an improvement in the automatic recloser integrator reset mechanism disclosed in Patent No. 2,897,- 315, filed by Frank L. Cameron on May 29, 1958, and

patented July 28, 1959, and assigned to the same assignee as the present application.

It has been suggested in the previously mentioned patent, as a means for providing the integrating mechanism of an automatic recloser with a substantially constant reclosing time, that the step-by-step advanoeable member of the integrator or counting mechanism be attached to the armature of a reset solenoid energizable by a time delay device which begins to time out in response to reclosure of the interrupter after an interruption operation and, after a predetermined time, effects operation of the reset solenoid if not additional interruption operation occurs.

A frictional brake is provided between the armature and coil of the reset solenoid to prevent overtravel of the movable integrator on each increment of advancement and to hold the integrator in the advanced position until an integrator reset operation occurs. Periodic adjustment of the frictional brake may be required.

It is an object of this invention to provide in an integrator for an automatic recloser and having a substantially constant resetting time, a latching device for holding the integrator in any of its advanced positions against a biasing means preventing overtravel of the integrator and tending to reset the integrator whereby automatic releasing of the latch mechanism a predetermined time after a reclosing operation will effect reset of the integrator mechanism in a rapid and positive manner.

In the practicing of this invention in accordance with one of its embodiments, a longitudinally movable integrator rod is advanced in a step-by-step fashion in response to each contact seperation operation of the automatic recloser to which it is attached for the purpose of actuating a recloser lock-out mechanism after a predetermined number of recloser operations. An integrator reset solenoid is provided in a time delay circuit operable to energize the solenoid a predetermined time after each automatic contact reclosing operation in the event a subsequent contact separation does not occur within the prescribed time limit. The armature of the solenoid is normally spring biased into engagement with the integrator rod which is provided with a ratchet. The extremity of the armature is provided with a roller whereby the armature and roller serve as a holding pawl mechanism engageable with the ratchet mechanism on the integrator rod to freely allow advancement of the integrator rod and at the same time prevent reset of the integrator rod until such time as the reset solenoid is operated to effect disengagement between the pawl and the ratchet. Operation of the solenoid in response to the time delay circuit effects disengagement between the holding pawl mechanism and the ratchet allowing the integrator rod to be rapidly reset under the urging of a spring biasing the integrator rod toward the reset condition. The reset spring performs the additional function of preventing overtravel of the integrator rod as it is incrementally advancied.

In accordance with a second embodiment of the in- "ice vention, shown in FIG. 4B, the integrator rod is provided with a single pawl while an elongated latch member, operated by the reset solenoid, is provided with the ratchet. The latch is pivoted at one end, spring biased at the other end into engagement with the pawl member and connected at a point intermediate the ends to the armature of the reset solenoid.

For a more complete understanding of the nature and scope of the invention, reference may be made to the following detailed description which may be made in conjunction with the accompanying drawing, in which:

FIGURE 1 is a sectional view of the automatic recloser;

FIG. 2 is another sectional view of the recloser;

FIG. 3 is a front elevat-ional view of the control panel shown in FIG. 2;

FIG. 4A is an enlarged side elevational view of one form of the integrator mechanism shown in FIG. 2;

H6. 413 is a fragmentary side elevational View of the integrator showing a modification of the integrator reset mechanism, and

FIG. 5 is a diagrammatic view of the automatic recloser shown in FIGS. 1 and 2.

Referring to FIGS. 1, 2 and 3, there is disclosed a polyphase recloser, designated generally by the numeral 10, which is identical in structure and operation to the recloser disclosed in Patent No. 2,858,395, filed by Alson Robert Harm et al., on August 24, 1956, and patented October 28, 1958, with the exception of certain additions to be specifically identified in the following description. Accordingly, reference is made to the entire specification of the aforementioned copending application for a detailed disclosure of the nature and operation of the individual parts of this automatic recloser.

For the sake of clarity of understanding, much of the substance of the hereinbefore identified patent is repeated herein.

In FIGS. 1, 2 and 3, it will be seen that the polyphase recloser comprises a substantially rectangular cover casting 12 having depending side portions 13 about the edge thereof with a flange 14 at the lower edge. The cover 12 is provided adjacent one edge with pairs of insulating bushings 15 and 16 for each of the three poles thereof. Only one pair of bushings 15 and 16 is shown, it being understood that additional poles and bushings are provided in the polyphase recloser as disclosed in the Harm et al. patent. Each pair of insulating bushings is arranged transversely of the longitudinal axis of the cover,

' the pairs being spaced from each other in the longitudinal direction to provide insulated entrances for conductors 18 and 19 of each phase through openings 17 in the castings. Each of the bushings 16 supports at its lower end an interrupter 20 which is connected by means of a condoctor 21 to a series type overcurrent trip element 22 supported at the lower end of the associated insulating bushing 15. The cover casting 12 is provided with a depending longitudinal intermediate wall or rib 23 having a flange 24 along its lower edge cooperative with the flange 14 so as to provide for securing an interrupter tank or casing 25 to the flanges 14 and 24 about the interrupters and overcurrent trip means, so that the interrupters and trip means may be positioned in insulating oil having a level designated by the dot-dash line 27. A separate tank 29' is secured to the casting 12 adjacent the tank 25 for enclosing an operating mechanism 3% shown in FIGS. 1 and 2 and time delay means 32 shown in FIGS. 1 and 3.

In FIG. 1 it will be seen that interrupter 20 includes contactsdi and a contact rod 48 disengageably associated therewith. The contact rod 48 is connected by means of an insulating link to a lever 66 secured to a shaft '75 rotatably mounted in suitable bearings positioned in bosses 71 depending from the cover casting. The shaft '7@ is provided with a lever 75 and connected by means areas The operating mechanism 3t? is'mounted in a frame 7 9 which, as shown in FIG. 1, is substantially 'U-shaped,

having a base 79 with upstanding sides 31 which are spaced apart and are secured by means of flanges 32 to bosses tifzldepending from the cover casting 12. (Cnly one. side 31, one flange 82 andpone boss 83 are shown.) The operating lever 78 is pivotally mounted on a shaft 85 mounted in frame 79, and is biased in a counterclockwise direction by means of a spring 86 mounted on link 76 in connectionwith the wall of recess 31. The lever 7 8 is releasably held in the closed position shown, with the spring 86 compressed, by means of a toggle linkage comprisingla'link. 89 connected to lever '78 by a pivot 9%, a toggle link 91 pivotally connected to the link 89 by a common pivot 92, and a latch lever 94, which is connected to the toggle link 91 by a pivot 95 and is rotatably mounted on a shaft 97 supported in the frame 79.

The toggle linkage in the position shown has the toggle link 91 resting against a stop 99, with the pivots'92 and 95 in overcenter positions. The pivot 95 is maintained in this position by means of a latch llliti which is pivotally mounted in the frame 79 on a shaft 102, and has a recess 103 which receives a roller 1% on a lower portion of the latch lever 94 The latch 1% is maintained in the position shown, by a toggle linkage comprising a link 1G7 pivotally connected to the latch at 1%, and a link 1163 connected to link 167 by a pivot 111 and rotatably supported in the frame 79 on a fixed pivot 113. A spring 114 connects link llll and latch 1%. A trip lever 115 is rotatably mounted on thepivot 113 having a projection 116 for actuating the common pivot 111 overcenter and laterally projecting pad 117 for operating the lever. An adjustable stop 118 normally engages pad 117 and holds the trip lever .115 in a position with the toggle levers 167 and 119 slightly overceriter.

When trip lever 115 is rotated counterclockwise, projection 116 breaks the togglearrangement of links 107 and 110, permitting latch 1% to rotate clockwise and release roller 105. Lever 94 rotates counterclockwise and pivot 95 moves farther overcenter, causing pivot 92 to drop undercenter and permit spring 86 to rotate operating lever 78 counterclockwise, moving link 76 to the left so as to rotate shaft 70 counterclockwise to lift contact rods 48, and causing links 107 and 11b to reset to the positions shown. 7 i

A shunt trip solenoid 120 is secured to the bottom of the mechanism frame 79, having an armature with a projection 121 which passes through an opening 122 in the bottom of the frame. An auxiliary trip lever 124 is pivotally mounted on the same pivot 113 as lever 115, and

is provided with a laterally extendingtab 125 disposed to be engaged by the projecting trip member 121 of the shunt trip solenoid, and also actuate the trip lever 115.

An auxiliary switch 131 (FIG. 3) is mounted on the frame 79 by means of a bracket 119 and operated from the lever extension 78a by means 'of a connecting link 123. Auxiliary switch 131 includes contacts 521: (FIG. which'are closed only when contacts 51 are open and also includes contacts 52a which are closed only when contacts 51 are closed.

The breaker may be reclosed automatically by means of a closing link 133 also connected to the common pivot 92 and having a pin 139 at its lower end which is free to move in an arcuate slot 140 in a guide member 142. The closing link 138 is provided witha shoulder 1 s.: disposed to be engaged by a roller 14.5 carried by a lever on a shaft 146 rotatably mounted on the sidewall 81 of the mechanism frame. A drum switch comprising a contact segment 'l l'i mounted on shaft 14-6, and a stationary contactmember M3 is utilized as a limit switch in controlling the operation of a motor 159, which is mounted on the bottom of the mechanism frame and connected by means of a Worm-gear drive (not shown) for rotating the shaft 1% to effect reclosing;

In FIGS. 1 and 2, the overcurrent trip element 22, described in detail in the hereinbefc-re mentioned Harm et algpatent, has an armature 154 and an operating coil 151 shown schematically in FIG. 5.] The armature 154 of web 23, toarm pivotally mounted as by means of a shaft 160 supported from the cover casting 12 by means of a bracket 161 on a panel 162 secured to the current.

cover. The other pole units (not shown) are provided with similar overcurrent trip devices and shafts so that operation of their overcurrent relays are individual to the. particular ,pole units.

The control panel 162 is mounted in the mechanism tank 29, being secured to the cover 12 by means such as brackets 167 to a portion of the central web 23. On his panel are mounted the plurality of time delay means 32 individual to each of the interrupters 20 for controlling the opening thereof. As shown in FIGS. 2 and 3, and as described in detail in the hereinbefore mentioned Harm et a1. patent, each of the time delay means 32 may comprise a diaphragm type dashpot and a resilient lost motion connecting device lelproviding a resilient connection between the operating rod 175, which is connected to a crank lever 17s by a pivot 1'77, and the central boss 168. This provides for resilient lost motion permitting immediate operation of the overcurrent trip relays 22 in the event of an excessive fault of, for example, about ten times normal'current, thus modifying the normal inverse time-current characteristic thereof. Springs 178 are connected between a pin 179 adj'ustably mounted by means'of a nut 18@ and bracket 131 on panel 162 and tension lever 176' to adjust the current pickup value of the delay means.

Operation of the several members 183 to connect delay means 32 to provide delayed tripping is provided by means of a common pivotal delay control member 190, which is pivotally moutned on the panel 169 as shown in F168. 2 and 3 and extends longitudinally thereof.

Tripping of the operating mechanism is effected by means of projecting arms 192 on the operating members 175 which engage levers 193 on a common trip bar or shaft 1% extending longitudinally of the panel. The trip bar 1% is pivotally mounted on the panel by means of brackets 197, and extends longitudinally, having a trip extension arm 198 adjacent the operating mechanism 30 which engages the pad 117 when raised, and actuat es the trip lever to open the contacts.

Also mounted on the panel 162 is an air dashpot time delay device 200 as shown in FIGS. 2 and 3 of substantially the same type as the delay devices 32, the delay movement being provided for operation in the downward direction. This time delay device is operatively connected to an extension 78a of lever 78, a pin 2%, to effect by means of projecting shoulders 192 delayed operation of a microswitch 295 which is mounted on panel 162 by a bracket 205 and used to set up a reclosing circuit for the closing motor 150.

A ground fault trip device 206 substantially similar to the overcurrent trip device described in detail in Patent No. 2,691,709, which issued on October l2, 1954, to H. J. Lingal et al., but responsive to a lower value of current is mounted on the panel 162 as shown in FIG. 3, having a solenoid actuated trip member 206 for also operating an extension 193 of the common trip bar 196 to efiect separation of the contacts in response to a ground fault Bushing type current transformers 2d? are mounted on the lower ends of the insulating bushings 15 in the interrupter tank 25 for supplying current to the ground fault trip device 206.

In order to provide for locking the recloser open after a predetermined number of closely consecutive openings, there is provided an integrator 210. The integrator 210 comprises an advanceable counter or integrator member 216 slidably disposed in a support member 211. The counter member 216 is provided with longitudinally spaced teeth 217. A lever 222 pivotally mounted on arms 223 extending from the panel 162 carries a pawl member 225 disposed to engage the teeth 217 in succession when the lever 222 is rotated in a clockwise direction by means of operating links 226 which are connected to arms (not shown) which project from the previously described operating lever 78. The lower end of the counter member 216 extends through a guide bracket 215 fixed to the panel 162 vertically below the previously described upper support member 211.

Near the lower end of counter member 216 is a lateral projection 230 which is disposed to be engaged by a projection 22-9 of a lever 227 pivotally connected at 231 to a link 232 connected to the trip lever 124 by a pivot 235. The lever 227 is pivotally mounted on panel 162 by means of a bracket 233, as shown in FIGURE 3. In the event that the trip lever 124 is moved in a counterclockwise direction by the shunt trip solenoid 120, the link 227 will be raised by the auxiliary trip lever 124 to advance the counter member 216 immediately to the lockout position. In this lockout position a microswitch 240, which is positioned to be engaged by the projection 230 after, for example, four closely successive opening operations of the recloser, interrupts the operating circuit for the closing motor 150 to prevent reclosing, and thus locks the recloser open.

The counter member 216 has thereon an adjustably positioned cam member 243. The cam member 243 engages and positions a cam lever portion of the control member 190 which is pivotally mounted on the panel 162, which, as shown in FIG. 2, actuates the time delay I control members 193 to disconnect the delay devices 32 and render them normally ineffective on the first one or two opening operations. 7

Directly associated withthe integrator rod 216 is an integrator return or reset mechanism comprised of a reset solenoid 270 and integrator return spring 271, operated by a time delay circuit comprised of a time delay relay 272 and a limit switch 273.

The reset solenoid 270 is attached by suitable bracket means to the panel 162 intermediate upper bracket 211 and lower bracket 215 and includes an armature 275 biased by a spring 276 into horizontal engagement with one of a number of spaced teeth 277, 278, 279 and 286 on the integrator rod 216. The armature 275 and the spaced teeth 277-280 are related to each other such that the armature 275 is effectively a holding pawl while the spaced teeth 277-280 comprise a ratchet associated with the holding pawl. Each ratchet tooth 2774.530 is provided with a horizontal bottom surface and an inclined upper surface to allow the integrator rod to move upwardly unhampercd by armature 275, whereby the inclined upper surface of each tooth acts to cam the armature inwardly of the solenoid 270 against the bias of spring 276. A roller 231 is provided on the end of armature 275 to permit relatively free upward movement of the rod 216 and further to minimize friction between the solenoid 275 and the ratchet teeth during the movement of the integrator rod 216 in an upward direction. It is seen that after a tooth has passed upwardly over the roller 281, the rod 216 is prevented from resetting by virtue of the bottom horizontal portion of the tooth engaged with the roller 281 whereby the integrator rod 216 is retained in the advanced position until the solenoid 270 is energized, in a manner to be hereinafter described, to retract armature 275 to release rod 216 and thus permit rapid reset of the integrator rod.

In order to prevent overtravel of the integrator rod 216 in its upward movement and to further provide rapid reset of the integrator rod when the solenoid 270 is energized, the previously mentioned reset spring 271 is provided at the lower end of rod 216 for compression between the lower support bracket 215 and a washer 283 pinned to the lower end of rod 216.

In the time delay circuit for energizing the reset solenoid 276 after a predetermined time in the event an additional separation operation of the recloser does not occur, the slow to operate relay 272 is fixed to the panel 162 in any suitable manner such as by brackets, and is provided with normally open contact 284 (FIG. 5) and is adjusted to provide a predetermined time delay, such as two minutes, before energization of the reset solenoid 270. The limit switch 273 is also attached to panel 162 in any suitable manner and includes a switch operating arm 287 releasably engageable with a tab 233 on the integrator rod 21.6. When the integrator rod 216 is in the lowest position representing zero count, tab 288 engages arm 287 to interrupt the energizing circuit for time delay relay 272 in a manner hereinafter described in detail.

Referring to FIG. 4B there is shown another embodiment of the integrator reset mechanism comprised of a latch member 3% constructed from flat stock material and having a plurality of spaced teeth 301 along its length, the spaced teeth comprising a holding pawl mechanism. A single toothed member 302 on the integrator rod and having a width less than the distance between the teeth, extends backwardly of the rod in the plane of the rod so as to be situated adjacent the teeth 301. The latch member 3% is pivotally mounted at the upper end, as at point 363 on a pivot support bracket 304 attached to the panel 162 (FIG. 4A).

As the rod 216' is advanced, the single toothed member 3492 advances successively over the teeth 301 to be held in the advanced position by the teeth 301. A spring 276' is provided between the lower end of latch member 36% and any suitable support member such as the outside panel 306 of the recloser 10. The spring 276' continuously biases the teeth 301 on latch member 300 into meshing engagement with the tab or tooth 30-2 on the integrator rod 216' to prevent reset of the integrator rod 216 until the solenoid 270' is energized.

By providing the series of teeth on the latch 300 in FIG. 4B rather than upon the integrator rod 216 as in FIG. 4A, there is provided a mechanism more susceptible to economical manufacture and of more durable and stronger parts.

Referring to FIG. 5, it will be seen that the recloser 10 is disposed to interrupt the circuit between conductors 18 and 19 of a three-phase circuit, the separable contacts being in this instance represented by the bridging type contact ltia in each instance. The trip relays 22 are shown with their trip coils 151 connected in circuit with the conductors 18 for operating armatures 149 which are operatively connected by means of dotted lines to actuate the common trip bar 196 through time delay devices 32, which have operating members 183 for disconnecting the delay means to obtain substantially instantaneous action, with the lever 190 for operating them actuated by cam 243 to the initial position as shown. Current transformers 207 are connected in parallel circuit relation to the trip coil 142 of the ground fault trip relay 266 for also operating the trip bar 196.

Operation of the trip bar 196 actuates trip lever 115, which breaks the toggle arrangement of levers 107 and 110 and disengages latch 1%, to permit the collapse of toggle levers 91 and 94 to the right, and hence permit toggle link pivot 92 to pass undercenter and provide for pivotal movement of operating lever 78 by its opening spring 86, which is compressed in the closed condition to reclose said contacts; counting means actuated by the operating means and including means advanceable to a different position in response to each contact separation operation of the operating means; said advanceable means including a ratchet thereon; a holding pawl normally engaging the ratchet for holding the counting member in the advanced position assumed on each advanced operation of the advanceable member; means biasing the advanceable means toward reset; a reset solenoid having an armature connected to said pawl to effect disengagement between said pawl and ratchet when energized only in the event that no additional contact separation operation occurs within a predetermined time after reclosing of the contacts following a first contact separation operation; time delay relay means for energizing said solenoid after a predetermined time delay; circuit means for operating said time delay relay means in response to the reclosing of the separable contacts; and means responsive to reset of the counting means to deenergize the time delay relay means.

5. A circuit interrupter, comprising: separable contacts; an operating mechanism for said contacts; electroresponsive means operable to actuate said mechanism to eiiect separation of said contacts; means responsive to separation of said contacts to actuate the mechanism to reclose said contacts; counting means actuated by the operating means and including means advanoeable to a different position in response to each contact separation operation of the operating means; said advanceable means including a ratchet thereon; a reset solenoid having an armature; a holding pawl for engaging said ratchet and connected to said armature for disengagement from said ratchet when the solenoid is energized only in the event that no additional contact separation operation occurs within a predetermined time after reclosing of the contacts following a first contact separation operation; means biasing said pawl into engagement with said ratchet; means biasing the advanceable means toward reset; circuit means for operating said solenoid; said circuit means including a normally open contact; time delay relay means operable after a predetermined time to close said contact in said circuit; circuit means for operating said time delay relay means and including a contact which is open only when the advanceable means is in the reset condition and including contact means which are closed only when the separable contacts are in the closed condition.

6. In a reclosing circuit interrupter, in combination, separable contacts; an operating mechanism for said contacts; electroresponsive means operable to actuate said mechanism to effect separation of said contacts; means responsive to separation of said contacts to actuate the mechanism to reclose said contacts; an integrator member advanceable step-by-step, each step occurring in response to a separation operation of the operating mechanism; spring-biased latching means for retaining the integrator member in its advanced position; spring means biasing the integrator member toward reset; and time delay relay means responsive to reclosing of the contacts for releasing said latching means to permit reset of the integrator member only in the event that no additional separation operation occurs within a predetermined time after reclosing of the contacts following a first contact separation operation.

7. A circuit interrupter, comprising: separable contacts; an operating mechanism for said contacts; electroresponsive means operable to actuate said mechanism to effect separation of said contacts; means responsive to separation of said contacts to actuate the mechanism to reclose said contacts, counting means actuated by the operating means and including means advanceable to a different position in response to each contact separation operation of the operating means; said advanceable means including a pawl thereon; holding means including a ratchet normally engaging the pawl means for holding the counting member in the advanced position assumed on each operation of the operating means; means biasing the advanceable means toward reset; solenoid means attached to the holding means to effect disengagement between the pawl and ratchet to permit reset of the advanceable means only in the event that no additional separation operation occurs within a predetermined time after reclosing of the contact following a first contact separation operation, and time delay relay means responsive to the reclosing of the contacts for controlling the operation of the solenoid means.

References Cited in the file of this patent UNITED STATES PATENTS

Claims (1)

1. A CIRCUIT INTERRUPTER, COMPRISING: SEPARABLE CONTACTS; AN OPERATING MECHANISM FOR SAID CONTACTS; ELECTRO-RESPONSIVE MEANS OPERABLE TO ACTUATE SAID MECHANISM TO EFFECT SEPARATION OF SAID CONTACTS; MEANS RESPONSIVE TO SEPARATION OF SAID CONTACTS TO ACTUATE THE MECHANISM TO RECLOSE SAID CONTACTS, COUNTING MEANS ACTUATED BY THE OPERATING MEANS AND INCLUDING MEANS ADVANCEABLE TO A DIFFERENT POSITION IN RESPONSE TO EACH CONTACT SEPARATION OPERATION OF THE OPERATING MEANS; SAID ADVANCEABLE MEANS INCLUDING A RATCHET THEREON; HOLDING PAWL MEANS NORMALLY ENGAGING THE RATCHET MEANS FOR HOLDING THE COUNTING MEMBER IN THE ADVANCED POSITION ASSUMED ON EACH OPERATION OF THE OPER-

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