US2911499A - Automatic recloser - Google Patents

Description

NOV. 3, 1959 CAMERON ETAL AUTOMATIC RECLOSER 3 Sheets-Sheet 1 Filed Dec. 16, 1957 Nov. 3, 1959 F. L. CAMERON ETAL 2,911,499

AUTOMATIC RECLOSER Filed Dec. 16, 1957 s Sheets-Sheet 2 Nov. 3, 1959 F. L. CAMERON ETAL 2,911,499

AUTOMATIC RECLOSER Filed Dec.

62. 3 Sheets-Sheet 3 United States Patent AUTOMATIC RECLOSER Frank L. Cameron, Irwin, and Alson R. Harm, Verona, Pa., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application December 16, 1957, Serial No. 703,195

8 Claims. or. 200-109 This invention relates to circuit breakers and more particularly to automatic reclosers. An object of the invention is to provide a polyphase recloser embodying current responsive relays to open all poles, and means for connecting time-delay means thereto to delay predetermined operations of the relays. 7 Another object of the invention is to provide a polyphase recloser embodying current responsive relays to effect opening of all poles, and adjustable means for connecting time-delay means thereto to delay predetermined operation of the relays.

Another object of the invention is to provide in a recloser for using current responsive relays with the interrupter for effecting separation of the contacts and for selectively and adjustably connecting mechanically therewith time-delay means for delaying predetermined operations of the relaymeans.

The invention, both as to structure and operation, together with additional objects and advantages thereof, will be best understood from the following detailed description thereof when read inconjunction with the accompanying drawings.

in said drawings:

Figure 1 is an elevational sectional view through one of the pole units showing the operating mechanism.

Fig. 2 is an elevational view showing the time-delay device. 7 V

Fig. 3 is an enlarged elevational view partly in section of the time-delay means of Fig. 2.

Fig. 4 is an enlarged partial view of the adjustable resilient connection of the time-delay means.

Fig. 5 isa front elevational view of the time-delay control panel shown in Fig. 2.

Fig. 6 is a schematic diagram showing the variation of the time-current characteristic curve.

Referring to Fig. 1, the polyphase recloser is an improvement over the recloser of copending application, Serial No. 606,009, filed August 24, l956,,by A. R. Harm, AlvinW. Ogg and Kenneth L. Niebauer, now Patent No. 2,858,395, issued October 28, 1958. The recloser includes a cover casting 12 to which is secured two tanks 25 and 29 which'house respectively a multipole recloser indicated generally at 10 and an operating mechanism 30, Fig. 1, and time-delay means 32 (Figs. 2 and 5). The tank 25 is filled with oil to a level indicated at- 27. Mounted in the cover 12 is a pair of insulating bushings 15 and 16 for each of the three poles of the recloser (only one pair being shown), through which bushings extend conductors 18 and 19. At their lower ends the bushings 16 support interrupters indicated generally at 20 each of which is connected by-a conductor 21 to a series overload current trip element 22 which is supported at" the lower end of the bushing 15. The interrupter 20 is provided with resilient contact fingers 51 which cooperate with a contact rod 48 to open and close the circuit. The interrupter 20 is also provided with a plurality. of discs or plates, not shown herein, but which are fully disclosed in the aforementioned copending application.

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The rods 48 are connected by means of insulating links 65 to levers 66 secured to a shaft 70 which is rotatably. mounted in suitable bearings supported in bosses 71 depending from the cover 12. The shaft 70 is provided with a lever 75 which is connected by a link 76 to an operating lever 78 of the operating mechanism 30.

The operating mechanism 30 is mounted in the tank 29 in a U-shaped frame comprising spaced side members 81 (only one of which is shown) rigidly joined at their lower ends by a cross member or base 79. The side members 81 are secured by means of flanges 82 to bosses 83 on the cover 12. The operating lever 78 is pivotally mounted on a shaft 85 supported in the frame and is biased in a counterclockwise direction by a spring 86. The operating lever 78 is releasably held in the position shown against the force of the spring 86 by means of a toggle linkage comprising links 89, 91 and a latch 94. The toggle link 89 is connected to the operating lever 78 by a pivot pin 90 and to the toggle link 91 by a knee pivot pin 92. The other end of the link 91 is connected by a pivot pin 95 to the latch 94 which is pivoted on a shaft 97 supported in the side frames 81.

In the closed position (Fig. l), the toggle link 91 rests against a stop 99 with the pivot pins 92 and 95 overcenter above a line drawn through the center of the pin 90 and the shaft 97. The pivot pin 95 is releasably maintained in this position by means of a latch 100 pivotally inountedon a shaft 102 supported in the frame 81. The'latch 100 has recess 103'therein which engages a latch roller 105 on the latch lever 94. The latch 100 is releasably held in the position shown by a tripping toggle comprising links 107 and which are connected together by a knee pivot pin 111. The link 107 is pivotally connected by a pivot pin 108 to the latch 100 and the link 110 is mounted on a fixed pivot 113 in the frame 81. A spring 114 is connected under tension between the latch 1,00 and the'toggle link 110. A trip lever 115 rotatably mounted on the pin 113 is provided with a projection 116 for actuating the toggle 107-110 overcenter, and a portion 117 which normally engages a stop 118 to hold the trip lever 115 in the position shown.

When the trip lever 115 is rocked counterclockwise, the projection 116 breaks the tripping toggle 107110 permitting the latch 100 to rotate clockwise to release the latch roller 105. This releases the lever 94 which rotates counterclockwise moving the pivot 95 farther overcenter causing the knee pivot 92 to move downwardly overcenter whereupon the spring 86 acts to rotate the operating lever 78 counterclockwise. This moves the link 76 to the left rocking the shaft 70 counterclockwise to lift the contact rods 48 and open the contacts. When the toggle linkage 89-91-94 collapses downwardly, it moves the lever 94 to the position shown where the roller 105 is re-engaged by the notch 103 permitting the spring 114 to reset the tripping toggle 107-110.

A shunt trip solenoid 120 is secured to the base 79 of the frame and has an armature provided with a projection 121 extending through an opening 122 in the base 79. An auxiliary trip lever 124 pivotally mounted on the pin 113 is provided with a laterally extendingportion 125 disposed to be engaged by the projection 121 of the shunt trip solenoid armature to actuate the trip lever 115.

The auxiliary trip lever 124 has a lateral projection 127 disposed to be engaged by a manual trip lever 128 rotatably mounted on a shaft 129 for engagement by a lever 128' for effecting manual tripping of the recloser.

The breaker is automatically reclosed following an opening operation by means of a closing link 138, the upper end of which is pivotally connected to the knee 92 of the toggle 89-91 and has a pin 139 on its lower end which is movable in an arcuate slot 140 in a guide member 142. The closing link 138 is provided with a shoulder 143 disposed to be engaged by a roller 145 carried by a lever 144 on a shaft 146 which is rotatably mounted in the side members 81 of the frame. A drum switch comprising a contact segment 147 mounted on shaft 146, and a stationary contact member 148 is used as a limit switch for controlling the operation of a motor 150. The motor is rigidly supported on the bottom of the mechanism frame and is suitably connected by means of a worm gear drive (not shown) to rotate the shaft 146 and reclose the breaker.

The breaker is manually closed by operation of a manual closing link 136 which is pivotally connected to the knee of the toggle 89-91. The closing link 136 is slidable in a guide member 137 and disposed to be engaged and raised by a roller 126 on the lever 128. This straightens the toggle 89-91 and actuates the operating lever 78 to close the breaker. The shaft 129 is actuated by suitable means from a point externally of the breaker housing. This means is not shown herein but is fully disclosed in the aforementioned copending patent application.

The armature (not shown) of the tripping electromagnet 22 is connected by means of a rod 157 to a lever 159 (Figs. 1 and 2) pivotally mounted on a shaft 160 supported by means of a bracket 161 on a panel 162 secured to the cover casting 12. The other pole units of the breaker are provided with individual shafts 160 and 160" (Fig. supported in brackets 161' and 161" so that operation of their overcurrent relays 22 are individual to their particular pole units.

Mounted on the control panel 162 are a plurality of time-delay means 32 individual to each of the poles for controlling the opening thereof. As shown in Fig. 3, each of the time-delay means 32 comprises a dashpot having a main casting 163 with a flexible diaphragm 164 clamped thereto by means of a ring 165. The central portions of the diaphragm 164 is clamped between plates 166 and 167 by means of a nut 168 secured to a central boss 168 on the plate 167. A resilient lost motion connecting device or linkage 169 including a spring 170 compressed between a cap 171 and an adjustable spring seat 171' by' means of pins 172 and 172 secured to extensions 173 of the boss 168 and to the lower end of a rod 175, respectively. The pins 172 and 172' slide in slots 174 and 174 respectively in rod 175 and extension 173, as shown in Fig. 4, thus providing a resilient connection between the operating rod 175, which is connected to a crank lever 176 by a pin 177, and to the central boss 168. This provides for resilient lost motion permitting instantaneous operation of the overcurrent trip relays 22 in response to excessive fault currents of, for example, about ten times normal current. Springs 178 (Fig. 5) are connected between a pin 179 adjustably mounted by means of a nut 180 and a bracket on the panel 162 and the lever 176 to adjust the pickup value of the time-delay means. A control valve 182 (Fig. 3) is provided to adjustably vent the space between the diaphragm 164 and the casting 163 to vary the amount of time delay, or the inverse time-current characteristic.

7 vThe minimum value of overload current required for the'tripping electromagnet 22 to pick up and operate the trip mechanism to instantaneously trip the breaker is varied by adjusting the initial compression of the spring 170 (Figs. 3 and 4). Referring to Fig. 4, the spring seat 171 consists of a cup-shaped spring seat 151 threaded into an adjusting ring 153 and secured in its adjusted position by a set screw 155.

By backing out the set screw 155, the adjusting ring 153 can be rotated relative to the spring seat 151 to thereby raise or lower the spring seat. When the spring seat is raised, the compression of the spring 170 is increased thus increasing the minimum overload current required to instantaneously trip the breaker. If the spring seat 151 is lowered, the compression of the spring 170 is decreased which reduces the minimum 54 959 -a predetermined number of closelyconsecutive opening 4 g current required to instantaneously trip the breaker. After the spring seat is adjusted, the set screw is tightened to maintain the spring seat in the adjusted position.

When the series solenoid 22 (Fig. 1) is energized it exerts a force through the linkage 169 (Figs. 3 and 4) on the time-delay device 32. In response to this force the trip bar 196 through the trip arm 198 actuates the trip lever 115 (Fig. l) and effects opening of the recloser. The compression spring which is physically in series with the solenoid linkage 169 and the time-delay dashpot must transmit the force exerted by the solenoid 22 to the air dashpot 32. At lower values of fault currents the force exerted by the solenoid is insuflicient to cause compression and collapse of the spring 170. Thus the spring functions as a solid member and full time delay of the dashpot is realized. At higher values of fault currents, however, the pull exerted by the solenoid 22 is suflicient to cause the spring 170 to collapse, thus permitting, through the adjustable linkage 169, the trip bar to engage and actuate the trip lever 115 and trip the recloser, even though the diaphragm of the dashpot has not moved its full travel. By means of adjusting the initial compression of the spring 170, the force required to cause the spring 170 to collapse is controlled, thus changing the slope of the time current characteristic as shown in Fig. 6.

As shown in Fig. 6, the solid line curve A represents a characteristic curve of the recloser when a solid link is substituted for the spring 170. Curves B and C represent two of an infinite number of curves which result when the initial compression of the spring 170 is varied.

A latch member 183 (Fig. 3) pivoted on a pin 184 in the member 173 has a downwardly extending portion engaging the pin 172 to prevent upward movement of the pin 172 relative to the member 173. Counterclockwise movement of the latch member permits the pin 172 to move upwardly in the slot 185 (Fig. 4) and thus permits the link 175 to move freely without'being impeded by the time-delay device 32. Operation of the several latch members 183 is effected by means of a common delay control member pivotally mounted on the panel 162 (Fig. 2) and extends longitudinally thereof as shown in Fig. 5.

Tripping of the operating mechanism is effected by means of arms 192 (Fig. 5) on the operating members 175 which engage levers 193 on a common trip bar or shaft 196 extending longitudinally of the panel as shown in Fig. 5. The trip bar 196 is pivotally mounted on the panel by means of brackets 197 and has a trip arm 198 thereon adjacent the operating mechanism 30 which, when raised, engages the portion 117 on the trip lever 115 and actuates the latter to trip the mechanism in the previously described manner.

Also mounted on the panel 162 is an air dashpot timedelay device 200 (Figs. 2 and 5) of substantially the same type as the delay device 32. This time-delay device is operatively connected to an extension 78a of'the lever 78 by a pin 202 (Fig. 5) to elfectQby means of a projection 192', delayed operation of a microswitch 205 which is mounted .on panel 162 by a bracket 205' and used to setup a reclosing circuit for the closing motor 150 (Fig. 1).

Means is provided for locking the recloser open after operations. This means comprises an integrator or counter indicated generally at 210 (Fig.5) and consists of a cylinder 211 having a piston (not shown) movable therein. The cylinder 211 is mounted by means of a bracket 212 on the panel 162. The piston is connected to a counter member 216 which is advanced one step at each opening operation by an advancing mechanism indicated generally at 217' connected by a link 226 to arms 228 on the extension 78a of the mechanism operating lever 78.

A lateral projection 230 at the lower end of the counter member 216 is disposed to be engaged by a projection 229 of a lever 227 pivotally connected at 231 to a link 232 which is connected by a pivot pin 235 to the shunt trip lever 124. The lever 227 is pivotally mounted on a bracket 233 secured'to the panel 162. In the event that the trip lever 124 is moved in a counterclockwise direction by either the shunt trip solenoid 120, or the manual trip means, the lever 227 will be raised by thetrip lever 124 to advance the counter member 216 immediately to the lockout position. An elongated spring 234 provides a soft resilient reset bias for the counter member 216.

In the lockout position, the projection 230 engages and actuates a microswitch 240 after, for example, four closely successive opening operations of the; recloser, whether the recloser is tripped manually or by the shunt trip, solenoid 120. The microswitch 240 opens the operating circuit for the closing motor 150 to prevent reclosing, thus locking the recloser open. 7

A portion 245 (Fig. of the control member 190 is engaged by a portion (not shown) on the counter mem her 216 and causes the control member 190 to actuate the time-delay control members 183. (Figs. 2, 3 and 5) to disconnect the time-delay devices 32 and render them ineffective on the first one or two opening operations.

While the integrator or counting means 210 has been briefly described herein, a full understanding thereof may be had from the copending application Serial No. 606,- 009, in which the counting means is fully disclosed and described.

The invention provides a polyphase circuit interrupter having electromagnetic trip means and a time-delay device for controlling the operation of the trip means. A

resilient linkage connects the trip means to the timedelay device to permit instantaneous tripping operations. This linkage is adjustable to vary the minimum overload current required to instantaneously trip the breaker. Adjusting means is provided to vary the current pickup value of the time-delay device and also to vary the amount of time delay provided by the delay device.

We claim as our invention:

1. In a circuit interrupter, separable contact means, operating means releasable to efiect separation of said contact means, trip means operable to elfect release of said releasable means, electroresponsive means operable in response to overload currents to actuate said trip means, time-delay means operable to delay operation of said electroresponsive means in response to currents below a predetermined value, a connection including resilient means connecting said electroresponsive means to said time-delay means, said resilient means permitting instantaneous operation of said electroresponsive means in response to currents above said predetermined value, and adjusting means for adjusting the tension of said resilient means of said connection to vary the minimum overload current required to actuate said trip means and instantaneously trip said interrupter.

2. In a circuit interrupter comprising relatively movable contact means and means releasable to effect opening of said contact means, trip means operable to effect release of said releasable means, electromagnetic means operable in response to overload currents to actuate said trip means, a time-delay device operable to delay operation of said electroresponsive means in response to overload currents below a predetermined value, a resilient linkage interconnecting said electromagnetic means and said time-delay device, said resilient linkage permitting instantaneous operation of said electromagnetic means to instantaneously actuate said trip means in response to overload currents above said predetermined value, and adjusting means for adjusting the tension of said resilient linkage while the length of said linkage remains constant I 6 to vary the minimum overload required to actuate said trip means and instantaneously trip the interrupter.

3. In a circuit interrupter comprising relatively movable contact means and means releasable to etfect opening of said contact means, trip means operable to efiect release of said releasable means, electromagnetic means operable in response to overload currents to actuate said trip means, a time-delay device operable to delay operation of said electroresponsive means in response to overload currents below a predetermined value, means adjustable to vary the pickup current value of said timedelay device, a resilient linkage interconnecting said electromagnetic means and said time-delay device, said resilient linkage permitting instantaneous operation of said electromagnetic means to instantaneously actuate said trip means in response to overload currents above said predetermined value, and adjusting means on said linkage for adjusting said resilient linkage to vary the minimum overload required to actuate said trip means and instantaneously trip the interrupter.

4; In a circuit interruptercomprising relatively movable contact means and means releasable to effect opening of said contact means, trip means operable to effect release of said releasable means, electromagnetic means operable in response to overload currents to actuate said trip means, a time-delay device operable to delay operation of said electroresponsive means in response to overload currents below a predetermined value, means adjustable to vary the pickup current value of said timedelay device, means adjustable to vary the amount of time delay provided by said time-delay device, a resilient linkage interconnecting said electromagnetic means and said time-delay device, said resilient linkage permitting instantaneous operation of said electromagnetic means to instantaneously actuate said trip means in response to overload currentsabove said predetermined value, and adjusting means on said linkage for adjusting the tension of said resilient linkage to vary the minimum overload required to actuate said trip means and instantaneously trip the interrupter.

5. In a circuit interrupter comprising relatively movable contacts and operating means releasable to effect opening of said contacts, trip means operable to effect release of said releasable means, electroresponsive means operable in response to overload currents to actuate said trip means, a time-delay device operable to delay operation of said trip means inresponse to overload currents below a predetermined value, a resilient linkage including spring means having an initial tension connecting said electroresponsive means to said time-delay device, said spring means permitting instantaneous operation of said trip means by said electroresponsive means in response to overload currents above said predetermined value, and adjusting means mounted on said linkage for adjusting the tension of said spring means to thereby vary the minimum overload current required .to instantaneously operate said trip means.

6. In a circuit interrupter comprising relatively movable oontacts and operating means releasable to effect opening of said contacts, trip means operable to effect release of said releasable means, electroresponsive means operable in response to overload currents to actuate said trip means, a time-delay device operable to delay operation of said trip means in response to overload currents below a predetermined value, biasing means biasing said time-delay device against operation, means for adjusting said biasing means to vary the pickup current value of said time-delay device, a resilient linkage including spring means having an initial tension connecting said electroresponsive means to said time-delay device, said spring 7 means permitting instantaneous operation of said trip means by said electroresponsive means in response to overload currents above said predetermined value, and adjusting means mounted on said linkage for adjusting the tension of said spring means to thereby vary the minimum overload current required to instantaneously operate s'a'id trip means. a 7. In a circuit interrupter comprising relatively movable contacts and operating means releasable to efiect opening of said contacts, trip means operable to effect release of said releasable means, electroresponsive means operable in response to overload currents to actuate said trip means, a normally inefiective time-delay device operable to delay operation of said trip means in response to overload currents below a predetermined value, means actuated by said operating'means to connect said timedelay device to delay operation of said trip means, a resilient linkage including spring means having an initial tension connecting said electroresponsive means to said time-delay device, said spring means permitting instantaneous operation of said trip means by said electroresponsive means in response to overload currents above said predetermined value, and adjusting r'neansmounted on said linkage for adjusting the tension of said spring means to thereby vary the minimum overload current required to instantaneously operate said trip means.

8. In a recloser comprising separable contact means and operating means releasable to effect separation of said contact means, trip means releasably restraining said operating means and operable to effect release of said operating means, a current actuated relayhaving a coil connected in series relation with said separable contact means and a movable armature, a resilient linkage connected to effect operation of said trip means; delay means operable to delay operation of said relay in response to overload currents below a predetermined value and normally disconnected from said relay said resilient linkage permitting instantaneous operation of said relay in response to overload currents above said predetermined value, means for adjusting said resilient linkage to vary the current pickup value of said relay in response to over load currents above said predetermined value, and means actuated by said operating means to connect said delay means to delay movement of said armature on predetermined ones oi a series of operations.

v References Cited in the file of this patent UNITED STATES PATENTS Sandin a a1. Aug. 15, 1950 T remblay et al Mar. 12, 1957

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