US2792461A

US2792461A - Metal-clad switchgear

Info

Publication number: US2792461A
Application number: US476104A
Authority: US
Inventors: Russell E Frink; Olsson Paul
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1954-12-20
Filing date: 1954-12-20
Publication date: 1957-05-14
Anticipated expiration: 1974-05-14
Also published as: FR1147964A; JPS323070B1

Description

3 Sheets-Sheet 1 May 14, 1957 R. E. FRlNK ETAL METAL-CLAD SWITCHGEAR Filed Dec. 20. 1954 INVENTORS Russell E. Frnk 8\ P ul Olsson. BY

L ATTORNEY WiTNESSES A d/w Q @Mw 3 Sheets-Sheet 2 Filed Dec. 20, 1954 HE.. l V T la w/ Q wm .fx1 H F HAI QV? I n@ 1! l mw l\mn mw n /r I IIIIL Ill .Illl w :laILll H l Lm t( N Mlm .mai

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5 shets-sheet 5 Filed Deo. 20, 1954 Breaker Open lvIETAL-CLAD SWITCHGEAR Application December 20, 1954, Serial No. 476,104 l2 Claims. (Cl. 200-50) Gur invention relates, generally, to metal-clad switchgear and, more particularly, to levering devices and interlocking nechanisms for metal-clad switchgear having removable circuit breaker units.

in metal-clad switchgear a drive-in or levering device is usually provided for mechanically moving the circuit breaker unit between the test or disconnected position and the operating or connected position within the cell or housing. Also, an interlocking mechanism is provided which cooperates with the levering device to prevent movement of the breaker unit between the test and the operating positions if the breaker is closed and to prevent closing the breaker when it is at any point between the test and the operating positions. T he levering devices and interlocking mechanisms utilized previously have been somewhat complicated in structure. Furthermore, some of them have not functioned properly all times.

An obiect of our invention is to provide a levering device having a small number of parts for moving a circuit breaker unit within a switchgear cell.

Anc-ther object of our invention is to provide for holding the circuit breaker unit in the test position in the cell.

A further object of our invention is to provide a simple and effective interlocking mechanism for a removable circuit breaker unit.

Still another object of our invention is to coordinate the closing mechanism, the levering device and the interlocking mechanism for a circuit breaker unit in controlling the operation of the circuit breaker and the movement of the breaker unit within the cell.

t EL nited States Patent O Other objects of our invention will be explained fully l,

hereinafter or will be apparent to those skilled in the art.

In accordance with one embodiment of our invention, an interlocking link has one end connected to the breaker operating mechanism and the other end so engaging a levering device that operation of the levering device to move the breaker unit is prevented if the breaker is closed. Closing of the circuit breaker is prevented when it is at any point between the test position and the operating position in the cell. A spring-biased pin holds the levering device and the breaker unit in the test position and the operating position.

For a better understanding of the nature and objects of the invention, reference may be had to the following detailed description, taken in conjunction with the accompanying drawings, in which:

Fig. 1 is a view, partly in side elevation and partly in section, of a portion of a metal-clad switchgear structure embodying the principal features of the invention;

Fig. 2 is an enlarged View, in elevation, of the levering device and interlocking mechanism for the circuit breaker;

Fig. 3 is an enlarged View, in section, taken along the line III-III in Eig. 2; and

'icc

Fig. 4 is an enlarged view, in section, the line lV-IV in Fig. 2.

Referring to the drawing, and particularly to Fig. l, the structure shown therein comprises a portion of a metal-clad switchgear cell or housing 10 which may be constructed by securing sheet metal members 11 to angle frame members 12 in a manner well-known in the art. Vthe cell structure may rest upon beams 9 disposed upon a suitable foundation. The cell 10 comprises a circuit breaker compartment 13, and may include a current transformer compartment 14, a bus compartment 15, and/or an out-going cable compartment 16. The various compartments are separated by partition members 17, 1'8 and 19.

A circuit breaker unit 21 is disposed in the breaker compartment 13 and may be moved horizontally into and out of the cell on wheels 22 which run on rails 23 disposed at the bottom of the cell. One form of circuit breaker and operating mechanism therefore, which may be used, is that disclosed in Findley, Oggs and Florschutz Patent No. 2,515,994, issued July 18, 1950. A hinged door 24 is provided at the front of the cell to ermit the breaker unit to be withdrawn from the cell.

in accordance with the usual practice, the breaker unit is provided with primary disconnecting contact members 25 which are disposed to engage stationary contact members 26 which are mounted inside insulating sleeves 2? disposed inside the cell itl. The disconnecting contact members may be of the type described in Patent No. 2,376,818 issued May 22, 1945, to M. l. Rubel and assigned to the Westinghouse Electric Corporation.

A drive-in or levering device is provided for mechanically moving the circuit breaker unit 21 between the 0perating or connected position and the test or disconnected position within the cell 10. .in the present drawing, the circuit breaker unit is shown in the disconnected position. When the breaker unit is inserted to the connected or operating position the disconnecting contact members 25 engage the stationary contact members 26, thereby connecting the circuit breaker to power conductors 28 which are connected to the stationary Contact members 26.

ln the present structure the levering device comprises a pair of lever arms 31 which are secured to opposite ends of a horizontal shaft 32 rotatably mounted in the circuit breaker unit. The shaft 32 is driven by a combined interlocking and levering member 33 which is secured to the shaft 32 and operated by a handle rod or lever 34 in a manner which will be described more fully hereinafter. A roller 35 is provided at the end of each one of the lever arms 31 and is disposed in a raceway provided between

angle members

36 and 37 which secured to the side o-f the cell 10. Since a lever arm 31 and cooperating angle members are provided at opposite sides of the breaker unit a levering force is provided at both sides of the breaker unit.

it will be seen that when the shaft 32 is rotated to 'e the arms 31 in a direction indicated by the arrow i l, thc rollers 35 move in the raceways between

tte members

36 and 37 which, as previously explained, are secured to the side of the cell structure, thereby drawing the circuit breaker unit into the cell to the connected Y* sition. When the shaft 32 is rotated in the opposite rection, force is provided through the arms 31 to move tie breaker unit from the connected to the disconnected position shown in the drawings. As indicated by the 'broke-n lines, each roller moves through an angle slightly over degrees during the movement of the breaker unit from the disconnected to the connected position and moves the breaker a distance approximately twice the length of the arms 31.

As shown more clearly in Fig. 2 the shaft 32 is mounted taken along in bearing plates 38 which are attached to frame members 39 ofthe breaker unit by bolts 41. The arms 31 may be welded or otherwise secured to the shaft 32. Likewise, the interlocking member 33 and a spacing washer 42 are welded to the shaft 32. The interlocking member 33 has three substantially equally spaced holes 43 therein for receiving one end of the handle rod 34. The shaft 32 may be rotated by inserting the rod 34 in one of the holes 43 and moving the rod through an arc as indicated in Fig. l. The rod 34 may then be removed and inserted in another hole to rotate the shaft 32 still further. As previously stated, three holes are provided vin the member 33 for the rod 34, thereby permitting three strokes or operations to be utilized in moving the breaker unit between the connected and the disconnected positions. Y

l An interlocking link.44 has one end connected to an operating member 45 of the circuit breaker mechanism by means of a pin 46. The member 45 is preferably connected to a part of the closing mechanism for the circuit breaker whichV moves with the movable contact of the breaker, and it is pivotally mounted on a pin or shaft 47. As shown in Fig. 3 the member 45 moves through an arc between the breaker open and the breaker closed positions during closing of the contact members of the circuit breaker. Likewise, the member 45 moves from the breaker closed position to the breaker open position during opening of the circuit breaker. Thus, the interlocking link 44 is moved longitudinally during operation of the contact members of the circuit breaker. The longitudinal movement of the link 44 is permitted by an oblong opening 48 in the link through which the shaft 32 extends to support the other end of the link 44.

As shown in Fig. 4 one side of the interlocking member 33 has slots or grooves 51 and 52 disposed therein between raised

surfaces

53 and 54. In the present instance the slot 51 is slightly wider than the slot 52.

rthe interlocking link 44 has a lugV 55 on one side which is disposed to enter the slot 51 when the circuit breaker unit is in the'disconnected position as shown in the drawings. As shown in Fig. 4, one side of the lug 55 engages a surface 56 of the raised portion 53 of the member 33, thereby preventing further rotation of the member 33 in a counterclockwise direction as shown in Fig. 4. Thus further rotation of the arms 31 in a clockwise direction as shown in Fig. 3 is prevented. A positioning pin 57, which is biased upwardly by a spring 58, has entered a notch 59 in the periphery of the member 33 to hold the shaft 32 in this position. 57 is slidably mounted in a bracket 61 which is attached to the frame member 39 of the circuit breaker unit by meansof bolts 62.

When the contact members of the circuit breaker are closed the lug 55 on the interlocking link 44 slides i downwardly into the slot 51, thereby making it impossible to rotate the shaft 32 and the arms 31 to insert the breaker unit into the cell with the contact members of the circuit breaker closed, since the end of raised portion 54 will engage the lug 55 and prevent further rota tion. In this position, the roller 35 or lever 31 is opposite the inner side 36 of the raceway which is longer than the outer side 37, so that the breaker unit is blocked from moving back into connected position in the cell, if Vone should try to do that without using the levering-in mechanism. It will be noted that if the shaft 32 is rotated in a counterclockwise direction as shown in Fig. 3 until the pin 57 enters a second notch 63 in the member 33 there will be practically no forward motion of the breaker unit into the cell, but the rollers 35 Will have entered the raccways between the

angle members

36 and 37, the arms 31 having been moved to a horizontal position. Thus the circuit breaker unit is held or latched Yin thetestl position by means of the stop pin 57 which has entered the notch 63. The fact that the rollers 35 then engage the outer sideY 37 of the raceway prevents ac- The pin .f

cidental movement of the breaker unit out of the cell.

In this position the contact members of the circuit breaker can still be closed because of the width of the slot 5l in the interlocking member 33 which permits the lug 55 to slide downwardly in the slot 51 without engaging the raised portion 54 or" the interlocking member 33. T his position of the circuit breaker unit may be considered the test position and the contact members of the circuit breaker may be closed in this position. if it is desired to make the test position and the disconnected position coineide, the slot 5l may be made the same width as the slot 52, thereby preventing closing the breaker except in the connected and the disconnected positions. ln this case the notch 63 would be omitted from the member 33.

.if the member 33 is rotated further in a clockwise direction as shown in Fig. 4, orV a counterclockwise direction as shown in Fig. 3, the breaker unit is drawn into the cell by means of arms 31 and the roller 35 as previously explained. The closing of the contact members of the circuit breaker is prevented while the breaker unit is being moved between the test and the connected positions by the lug 55 on the interlocking link 44 engaging the circular surface 64 of the raised portion 54 of the interlocking member 33.

When the shaft 32 is rotated to its extreme position in which the lug 55 engages a surface 65 of the raised portions 53, the contact members of the circuit breaker can be closed since the lug 55 can slide downwardly into the slot 52. This is the connected or operating position of the circuit breaker unit. When the contact members of the circuit breaker are closed, rotation of the shaft 32 to move the breaker unit toward the disconnected position is prevented by the lug 55 engaging an end surface 66 on the raised portion 54 of the interlocking member 33. Itis impossible to move the circuit breaker to separate the primary disconnecting contact members when the Contact members of the circuit breaker are closed. Furthermore, it is impossible to close the contact members of the circuit breaker at any point between the test and the connected positions of the circuit breaker unit.

Position indicators

67 and 68 may be cast on one side of the interlocking member 33 to line up opposite a name plate on the frame and show Whether the breaker is in the connected position, the latched-in test position, or the E disconnected position in which the breaker may be rolled out of the cell.

Additional notches

69 and 71 are provided in the periphery of the member 33 to hold the circuit breaker unit while the handle rod 34 is being changed from one hole 43 to another in the member 33. A notch 72 is provided for the pin 57 to hold the circuit breaker unit in the operating position.

The breaker unit may be provided with a secondary disconnecting device of the type disclosed in Haylord Patent 2,276,968, issued March 17, 1942. Thus, the necessary control circuits for controlling the operation of the circuit breaker mechanism may be established when the breaker unit is in the test position.

From the foregoing description, it is apparent that We have provided a levering device and an interlocking mechanism which cooperate to provide a mechanical means for removing and replacing a circuit breaker unit in a switchgear cell and which prevents movement of the circuit breaker unit between the test and the connected positions when the contact members of the circuit breaker are closed. Furthermore, the closing of the breaker contact members is prevented when the circuit breaker unit is at any point between the test and the connected positions. The levering device and the interlocking mechanism are relatively simple in structure and are suiciently strong to preclude breakage of the mechanism under reasonable usage.

Since numerous changes may be made in the abovedescribed construction, and diierent embodiments of the invention may be made without departing from the spirit and scope thereof, it is intended that'all matter contained vin the foregoing description orslrown'in'the accompanying drawing shall be interpreted as illustrative iand not "in a limiting sense.

We claim as our invention:

1. in a switchgear structure in combination, a cell, a circuit breaker unit disposed in the cell, operating means for closing contact members of the breaker, a rotatable levering device for moving the breaker unit 'between Aconnected aud test positions inthe cell, an `interlocking link having one end connected to said operating means, the other end of said link being actuated by said operating means to engage the ievering device 'to preventmovement of the breaker unit if the contact members of the'breakeiare closed, and stop'means on the levering ldevice engaged by said interlocking link to limit'the rotation of the levering' device.

2. In a switchgear structure in combination, a cell, a circuit breaker unit disposed in the cell, operating means for closing contact members of the breaker, a

rotatable levering device for moving the breaker unit fbetween'connected and test ,positions in the cell, 'aniinterlocking link having one end connected to said operating means, the other end of said link engaging the levering 'device to prevent closing the contact members of the breaker by said operating means when the breaker unit is at any point between the connected position and the test position, and stop means on the levering device engaged by said interlocking link to limit the rotation of the levering device.

3. in a switchgear structure in combination, a cell, a ycircuit breaker unit disposed in the cell, operating means for closing contact members of the breaker, a rotatable levering device for moving the breaker unit between connected. and test positions in the cell, an interlocking link having one end connected to said operating means, said link being actuated by said operating means to prevent movement of the breaker unit when the contact members of the breaker are closed, said link having means thereon engaging said levering device tto prevent closing the contact members of the breaker when the breaker unit is at any point between the connected position and the test position, and stop means on the levering device engaged by said interlocking link to limit the rotation of the levering device.

4. in a switchgear structure in combination, a cell, a circuit breaker unit disposed in the cell, operating means for closing contact members of the breaker, a rotatable levering device for moving the breaker unit between connected and test positions in the cell, an interlocking link having one end connected to said operating means, said link being moved longitudinally by said operating means to engage the levering device to prevent operation of the levering device when the Contact members of the breaker are closed, and said levering device having means thereon engaging said link to prevent closing the contact members of the breaker by said operating means while the levering device is being operated to move the breaker unit.

5. In a switch gear structure, in combination, a cell, a circuit breaker unit disposed in the cell, a pivoted operating lever for closing contact members of the breaker, a rotatable shaft having one or more arms secured thereto engageable with the cell to move the breaker unit between predetermined positions within the cell, levering means secured to the shaft for rotating the shaft, an interlocking link having one end attached to said operating lever and the other end movably supported by said shaft, said link being movable longitudinally by said operating lever to engage the levering means to prevent rotation of the shaft to move the breaker unit when the contact members of the breaker are closed.

6. In a switchgear structure7 in combination, a cell, a circuit breaker unit disposed in the cell, a pivoted op erating lever for closing contact members of the breaker, a rotatable shaft having one or more arms secured thereto engageable with the cell to move the breaker unit between predetermined positions lWithin the cell, levering .means ysecured to the shaft for rotating the shaft, an interlocking link having one end attached to said operating lever 'and the 'other end movably supported by said shaft, said link being movable longitudinally by said operating leve'rto engage the levering means'to prevent operation of the levering means when the contact members of the breaker are closed, and 'said levering means having a raised portion thereon for engaging said link vto prevent 'closing the contact members of the Ybreaker while the breaker by said operating lever unit is being moved between said predetermined positions.

7. In a switchgear structure, in combination, a cell, a circuitbreaker unit disposed in the cell, a pivoted operating lever for closing contact members of the breaker,

Yarotatable shaft having one or more arms secured thereto and engageable with the cell to move the breaker unit between predetermined p'ositionswithin'the cell, interlock- -in'g means *secured to the shaft, an interlocking link having one end pivotally attached to said operating lever,

said link having an oblong opening adjacent the other end, said shaft extending through said opening to support said other end of the link, and said link being movable longitudinally by said operating lever to engage said interlocking means and prevent movement of the breaker unit by rotation of said shaft when the contact members of the breaker are closed.

8. In a switchgear structure, in combination, a cell, a circuit breaker unit disposed in the cell, a pivoted operating lever for closing contact members of the breaker, a rotatable shaft having one or more arms secured thereto and engageable with the cell to move the breaker unit between predetermined positions within the cell, interlocking means secured to the shaft, an interlocking link having one end pivotally attached to said operating lever, said link having an oblong opening adjacent the other end, said shaft extending through said opening to support said other end of the link, said link being movable longitudinally by said operating lever to engage said interlocking means and prevent movement of the breaker unit by rotation of said shaft when the contact members of the breaker are closed, and blocking means on said interlocking means for engaging said link to prevent closing the contact members of the breaker by said operating lever while the breaker unit is being moved between said predetermined positions.

9. in a switchgear structure, in combination, a cell, a circuit breaker unit disposed in the cell, a pivoted operating lever for closing contact members of the breaker, a

f rotatable shaft having one or more arms secured thereto and engageable with the cell to move the breaker unit between predetermined positions within the cell, interlocking means secured to the shaft, an interlocking link having one end pivotally attached to said operating lever, said link having an oblong opening adjacent the other end, said shaft extending through said opening to support said other end of the link, said link being movable longitudinally by said operating lever to engage said interlocking means and prevent movement of the breaker unit by rotation of said shaft when the Contact members of the breaker are closed, said interlocking means having spaced means thereon corresponding to said predetermined positions of the breaker unit, and spring-biased means engaging said spaced means to hold the breaker unit in said predetermined positions.

lt). In a switchgear structure, in combination, a cell having spaced members therein, a circuit breaker unit disposed in the cell, a pivoted operating lever for closing contact members of the breaker, a rotatable shaft having two arms secured thereto and engageable with said spaced members in the cell to move the breaker unit between test and connected positions within the cell, an interlocking member secured to the shaft and having spaced slots therein corresponding to the test and the connected positions of the breaker unit, an interlocking link having wat@ .one end pivotally attached to said operating lever and an 'oblong opening adjacentrthe other end, said shaft ex- Ytendingthrough said opening to support said other end sition between said spaced members in the cell to hold the breaker unit in the test position, a notch on the interlocking member corresponding to the test position of tlie breaker unit, and a spring-biased pin entering said notch to retain the shaft in the test position.

11.*In a switchgearlstructure, Yin combination, a cell, a circuitA breaker unit disposed in the cell, operating means for closing` contactV members of the breaker, a

.rotatable levering device for moving the breaker unit vbetween connected and test positions in the cell, interlocking means cooperating. withv saidlevering device to prevent movement of the breaker unit by rotation of the levering device if the contact members of the breaker are closed, and spring-biased means for releasably engaging the levering device to retain the breaker unit in the test position in the cell.

l2. In a switchgear structure, in combination, a cell, a circuit breaker unit disposed in the cell, operating means for closing contact members of the breaker, a rotatable levering device for moving the breaker unit between predetermined positions within the cell, interlocking means cooperating with said levering device to prevent movement of the breaker unit by rotation of the levering device if the contact members of the breaker unit are closed, and spring-biased means for releasably engaging the levering device to retain the breaker unit in said predetermined positions.

References Cited in the le of this patent UNITED STATES PATENTS 2,544,314 Hebbel Mar. 6, 1951 ipa m