US3021400A

US3021400A - Manually controlled contact actuatin gmechanism

Info

Publication number: US3021400A
Application number: US14408A
Authority: US
Inventors: Jr Edwin C Goodwin
Original assignee: Allis Chalmers Corp
Current assignee: Allis Chalmers Corp
Priority date: 1960-03-11
Filing date: 1960-03-11
Publication date: 1962-02-13
Anticipated expiration: 1979-02-13

Description

Feb. 13, 1962 c, GOQDWIN, JR 3,021,400

MANUALLY CONTROLLED CONTACT ACTUATING MECHANISM 5 Sheets-Sheet 1 ulllllllllllllllllllll Filed March 11, 1960 amt OM11 60mm .2. 5mm 31.

Feb. 13, 1962 E. c. GOODWIN, JR 3,021,400

MANUALLY CONTROLLED CONTACT ACTUATING MECHANISM Filed March 11, 1960 5 Sheets-Sheet 2 cv/mvmliorl 50140144 .8. 90001442144 JP.

Feb. 13, 1962 E. c. GOODWIN, JR 3,021,400

MANUALLY CONTROLLED CONTACT ACTUATING MECHANISM Filed March 11, 1960 5 Sheets$heet 3 QmAMMlb/i Edwin 1 5 00144 144 Jfi.

3,021,400 MANUALLY CONTROLLED CONTACT ACTUATING MECHANISM Filed March 11, 1960 Feb. 13, 1962 E. c. soonwm, JR

5 Sheets-Sheet 4 9mm 25404-4412. 2mm .712. 1/1 MK?! I F eb- 13, 19 E. c. GOODWIN, JR

MANUALLY CONTROLLED CONTACT ACTUATING MECHANISM 5 Sheets-Sheet 5 Filed March 11, 1960 lM/mmrl X 50mm ,8. 90mm J2.

m 52 whorl/mg 3,021,400 I MANUALLY CONTROLLED CONTACT ACTU- ATING MECHANISM Edwin C. Goodwin, Jr., Canton, Mass, assignor to Allis- Chalmers Manufacturing Company, Milwaukee, Filed Mar. 11, 196 0, Ser. No. 14,408

13 Claims. (Cl. 200-50) This invention relates to circuit breaker structures for mounting in a cubicle and more particularly to a new and improved integrated transmission mechanism for selectively actuating a circuit breaker racking mechanism and an arcing contact controlling mechanism. This integrated action mechanism is particularly concerned with but not limited to manually operatedlow voltage air circuit breakers of the type used in metal enclosed drawout switchgear.

A low voltage air circuit breaker is composed essentially of relatively fixed and movable contact structures operated by a mechanism which may be either motor, solenoid or manuallyactuated. These components are mounted on a supporting frame. In order to facilitate the installation of this breaker it may be equipped with suitable wheels and a racking device both attached to the supporting frame. When a breaker of this type is installed in metal enclosed drawout switchgear, it is first placed in the free position with the wheels on the extended drawout supporting structure and then racked through the disconnect and test positions to the connected position, in which position its arcing contacts may be closed.

Maintenance operation of a circuit breaker for checking the conditions of its contacts, the lead relationship between its arcing and main contacts, and synchronization of the contact make position on all three phases of the circuit breaker structure is essential for maintaining the breaker in a safe operating condition and is therefore usually provided in one form or another on most circuit breaker structures.

Therefore, a circuit breaker structure is needed by the trade employing a'permanently attached manually operated handle or crank which:

(1) Racks the circuit breaker into a cubicle from the circuit disengaged position through the disconnect and test positions to the circuit breaker connected position,

, or the reverse thereof; i i

(2) Overcomes the primary and secondary cont-act reaction when entering the connected position;

(3) Charges a stored energy type breaker operating mechanism; and 1 (4)-Closesoropens the breaker contacts slowly for "maintenance inspection.

Thus, all of the breaker functions usually' accomplished through the use of varioushandles or levers are provided inherently through themedium of one handle and integrated manual operation is realized thereby.

In accordance with the invention cl ed improved frame mounted circuit breaker structure is provided for mounting in a cubicle. This. structure comprises a pair of cooperating relatively movable arcing contacts mounted on the frame. A closing device comprising a first'spring means is provided for closing the contacts-upon bias thereof and an opening device com prising a second spring means is provided for opening the contacts to a predetermined distanceupon bias thereof. The spring closing means is connected to the spring opening means for biasing the opening means upon closure of the contacts. Means are provided for rendering the closing means ineffective when the spring closing means is in its biased position. A racking means is mounted on the frame for cooperating with the cubicle upon actuation and dual purpose crank or lever means is provided for selectively actuating the racking means and the cona new and 3,021,400 Patented Feb. 13, 1962 tacts. This crank or lever means is rendered elfectivc only upon ineffectiveness of the closing means for -actuat-.

ing the contacts when separated in opening and closing directions. 1

It is, therefore, one object of this invention toprovide a new and improved contact controllingrnechanism for a circuit breaker structure.

Another object of this invention is to provide a new and improved contact controlling mechanism in which a spring biased contact closing mechanism can be readily controlled to reduce contact closing speed sufiiciently' to examine minutecontact motion.

A further object of this invention is toprovide a new and improved contact controlling mechanism in which spring biased contact closing or opening action can be stopped and held at any point so that lead of the arcing contacts over the main contacts or other settings can be precisely measured.

A still further object of this invention is to provide a new and improved contact controlling mechanism in which arcing contacts being closed by hand may be tripped open by a spring load at any point during contact separation without injurious results to either the contact operating mechanism or operator.

Objects and advantages other than those set forth will be apparent from. the following description when read in connection with the accompanying drawings, in which:

FIG. 1 is'a vertical cross sectional view partly in elevation of a circuit breaker structure taken along the line I--I of FIG. 2 utilizing a transmission mechanism employing the present invention and showing the contact closing and opening springs in their biased and unbiased positions, respectively;

FIG; 2 is a partial front elevational view of the circuit breaker structure shown in FIG. 1; j FIG. 3 is an enlarged partial view of the circuit breaker racking and arcing contact controlling mechanism shown in FIG. 2 in the arcing contact controlling position;

FIG. 4 is an enlarged partial view similar to FIG. 3 showing the circuit breaker and arcing contact controlling mechanism in the racking position;

FIG. 5 is a diagrammatic view similar to FIG. 1 showing the circuit breaker contacts and'controlling mechanism in a partly closed position; and i FIG. 6 is a diagrammatic view similar to FIG. 5' show;- ing the circuit breakercontacts and controlling mechanism just short of contact closed position. I

Referring more particularly to the drawings by characters of reference FIGS. l-6 illustrate a circuit breaker 10 utilizing an integrated transmission mechanism 11 for selectively actuating a 'circuit breaker racking mecha nism 12 and an arcing contact controlling mechanism 13.

The transmission'mechanisrn 11 comprises a pinion or driving shaft '14 having fixedly mounted thereon a first by means of a manually rotatable crank or handle 18.

Rotation of handle 18 delivers energy through shaft 19, worm 20 and worm gear 21 into shaft 22 to chain sprocket 23. A flexible drive chain 24 connecting

sprockets

23 and 15 causes rotation of driving shaft 14 in the same a a manner as does motor 17.

This manually integrated actuating mechanism compris ing shaft 19 and worm 20 is supported in such a manner that worm 20 is maintained in continuous engagement with worm gear 21 which is supported by but not permanently attached to shaft 22. To shaft 22 are fastened

pins

25, 26, 27, 28 and 29. Pin 28 engages a slot 30 in hub 31 of worm gear 21 at all times While

pins

25 and 29 may be caused to engage a slot 32 in hub 33 of sprocket 23 and a slot 34 in a hub 35 of rotatablymounted racking crank 36 by displacing shaft 22 to the left and right respectively as shown in FIGS. 3 and 4.

Displacement of shaft 22 is effected by movement of a selector lever 40 acting through a pin 41 and a block 42. Block 42 is supported by but not attached to shaft 22 and pin 41 extends from block 42 into a loose fitting aperture in lever 40. Block 42 is contained between

pins

26 and 27 on shaft 22. In the position shown in FIG. 2, handle 18 is inoperative as far as conveying motion to driving shaft 14 since shaft 22 is disengaged from sprocket 23. In the manual driving position lever 40 is moved from the position shown in FIG. 2 to the left as shown in FIG. 3 so that shaft 22 and sprocket 23 are interconnccted. During the time that handle 18 is rotated to drive shaft 14 the shaft of the electric motor 17 is also rotated because they are directly connected together. Further, during the time that motor 17 is driving shaft 14 sprocket 23 and chain 24 are also driven although at this time lever 40 has disconected shaft 19 from shaft 14.

Rotation of driving shaft 14 and gear 16 by chain 24 causes rotation of a gear 45 which is in meshing engagement therewith and, for example, may be rotatably mounted on a bearing pin or shaft 46. Gear 45 is provided with a driving pin 47 positioned to engage with a corresponding pin 48 on an eccentric 49. Eccentric 49 is supported by shaft 46 for rotation thereon. Rotation of gear 45 engages pin 47 on gear 45 with pin 48 on eccentric 49 and revolves eccentric 49 clockwise as shown in FIG. 1 about its fixed center, which is the center of shaft 46, driving a connecting rod 50 to the right. Connecting rod 50 is fixedly mounted on ahousing 51 supported by eccentric 49 and rotatably movable therewith during at least a part of the cycle of rotation of eccentric 49, as is well known in the art.

The motion of connecting rod 50 to the right compresses a pair of load springs (stored energy devices), 52 and 53 as shown in FIGS. 1 and 2 that function as a unit through link mechanism 54 and bar 55. At the instant that springs 52 and 53 are fully charged, latch roll 56 affixed to housing 51 engages a prop latch 57, thus holding the fully charged springs latched and ready to be discharged to perform a useful function, for example, closing the movable cooperating arcing contacts 70 and 71 of a circuit breaker. The prop latch 57 may be released by a solenoid mechanism 60. which upon movement of its armature rod 61 to the right as shown in FIG. 1 actuates prop latch 57 through a lever 62 and shaft 62. to rotate it clockwise, releasing latch roll 56,, thereby permitting housing 5.1 and connecting rod 50 to rotate under the force of springs 52 and 53. Once the stored energy or load springs 52 and 53 have been released the springs can again be recharged automatically by motor 17 or manually by handle 18 as explained above.

To prevent overloading of the spring charging system when latch roll 56 engages prop latch 57, gear 45 which is. driven by the driving, shaft 14 is shaped to disengage from gear 16 on shaft 14 at the fully charged position of the stored energy springs 52 and 53. This disengagement is accomplished by the removal of asegment of'the teeth from the periphery of the gear. Flexible teeth 63 (shown in FIG. 1) are provided at the end of the. open segment to facilitate reengagement of the

gears

16 and 45 at the beginning of each. cycle of meshing engagement. As pin 48 on eccentric 49 is moved clockwise to the left as shown in FIG. 1 when connecting rod 50 is releasedfor utilizing the stored energy of springs 52 and 53, gear 45 becomes free to rotate and is caused to reengage with gear 16 and driving shaft 14 by a spring 64 attached to bias lever 65 which acts against a pin 66 fixed to gear 45.

The flexible teeth 63 are detachably mounted along only a portion of a second part of the periphery of gear 45 by means of bolts 67 which may threadedly engage with suitable openings along the periphery of the gear structure; Teeth 63 are shown as formed of overlapping metallic strip material of resilient properties which are so arranged as to have spaced teeth gear edges. The span of flexible teeth are arranged in the open segment of the tooth periphery of gear 45 adjacent one end of the normal gear teeth 68 of gear 45. Gear teeth 63 arranged along a first part of the periphery of gear 45 have solid tooth segments while teeth 63 are flexible so as to yield if necessary upon engagement with the teeth on pinion or gear 16 or upon initial movement of shaft 14 to automatically position gears 16 and 45 in proper meshing engagement at the start of each driving cycle of shaft 14. This arrangement of flexible teeth at the beginning part of a span of teeth provides unimpeded reengagement of the charging motor pinion gear 16' with the charging mechanism for springs 52 and 53 immediately after each energy releasing action of the prop latch mechanism 57.

As shown in FIG. 1 the arcing contact mechanism including the pair of cooperating contacts 70 and 71 is in the contact open position with the stored energy springs 52 and 53 charged. Springs 52 and 53 are connected to the arcing contacts by means of a bell crank 72 pivotally mounted at 73 to the frame of the circuit breaker. One end of bell crank 72 is pivotally connected by pin 74 to link mechanism 54 and by a pin '75 to link 76. Link 76 is pivotally connected at 69 to a rotatable closing cam 77 which acts against toggle roll 78 moving a toggle linkage comprising toggle arms 79 and 80 to the right as shown in FIG. 1 about a releasable center point 81 to close the arcing contacts. When the arcing contacts are in their closed position the toggle is arranged in an overcenter position in the usual manner. The closing cam 77 will remain in its upper position reached when forcing the toggle linkage to its overcenter position until the closing springs 52 and 53 are recharged. Recharging of the closing springs 52 and 53 will rotate bell crank 72 in the counterclockwise direction to the position shown in FIG. 1 thereby drawing the closing cam '77 down to the position shown for another arcing contact closing operation.

The'opening and closing of the arcing contacts by the toggle linkage comprising the toggle arms 79 and 80 cause rotation of a lever arm which is connected at one end to arm 79 and is fixedly mounted for rotation on a shaft 91 near the other end. Lever arm 90 has a protruding member 92 which upon counterclockwise rotation of lever arm 90 during a closing operation of contacts 79 and 71 compresses a spring 93. Upon release of the bias of springs 52 and 53 contacts '76 and 71 are closed and spring 93 compressed.

Opening (tripping) of the circuit breaker contacts 70 and 71 from the position shown in FIG. 6 to the position shown in FIG. 1 is accomplished by the release of trip latch 94. Trip latch 94 is held in the position shown in 'FIG. 1 by a trip shaft 95. Shaft 95 has a given contour such that in one position it holds trip latch 94in a given position and when rotated to another position releases the latch. Trip shaft 95 is rotated counterclockwise by'action: of a shunt or overcurrent' trip device 96 or a manual trip'device: 97. This rotation of the trip shaft 95 permits trip latch 94 to rotate counterclockwise about its fixed center 98 by the load bias of toggle latch 99. Thus, togglelatch 99 is released and permitted to rotate clockwise about center 100 under the bias of spring 93. Releasably restrained center 81 is now free to rotate with the toggle latch 99 permitting the force of spring load 93 to move crank or lever arm 90 clockwise to collapse the toggle formed by toggle arms 79 and 80 to the position shown in FIG.- 1. The rotation of arm 90 and movement of a link 102, connecting toggle arm 79 and arm 90 tothe movable arcing contact 70, to the left opens the circuit breaker contacts. The resetting sequence of the trip latch 94, toggle latch arm 90, and toggle linkage comprising toggle arms 79 and 80 is dependent on the position of the stored energysprings 52 and 53. With the springs 52 and 53 charged, the latches and toggle mechanism will immediately be reset by the bias ofspring 101 as shown in FIG. 1. With the springs 52and 53 discharged, the closing cam 77 will hold the toggle mechanism trip free until the charging sequence is started at which time the closing cam will be withdrawn permitting the toggles and latches to reset.

When the circuit breaker ismounted in or removed from a cubicle 88 the circuit breaker is racked in and out by the racking mechanism 12. Racking mechanism 12 comprises a pairof pivotally mounted racking cranks 82 (one of which is shown in FIG. 1) each provided with a slot 83 at one end thereof for engaging with fixed pins 86 one of which is shown in FIG. 2 attached to the sides of cubicle 88. Cranks 82 are fixed to a driven shaft 84 I I and are rotated by an arm 85 also fixed to shaft 84. Arm 85 is actuated by racking crank 36 through racking links 87. Racking crank 36 is rotatably mounted on shaft 22.

In order to actuate the racking mechanism 12 the selector lever 40 is moved to the racking position shown in FIG. 4. In this position shaft 22 is moved to the right and pin 29 engages with slot 34 of hub 35 of arm 36.

Upon rotation of shaft 22 arm 36 is rotated to actuate tion of gear 45 engages pin 47 with pin 48 on eccentric 49 which revolves eccentric 49 clockwise about shaft 46 driving the connectingrod 50 to the right. The motion of the connecting rod 50 to the right compresses springs 52 and 53. At the instant springs 52-and 53 are fully charged, latch roll '56 affixed to connecting rod housing 51 engages prop latch 57 thus holding the fully charged springs latched and ready to be discharged to close the breaker by release of prop latch 57 by the solenoid mechanism 60. Once the stored energy springs have been released and the breaker closed, springs 52 and 53 are again recharged automatically bythe motor drive unit, thereby providing a standby supply of stored energy, if the se lector lever is in the neutral position.

Manual charging of the stored'energy springs 52 and 53 is accomplished by moving the selector lever 40 to the charge position shown in FIG. 3 and rotating handle 18 counterclockwise to engage shaft 22 through pin 25 to sprocket 23. This action now makes the handle an in-' tegral part of the charging scheme. Rotation of handle 18 delivers energy through shaft 19, worm 20 and worni gear 21 into shaft 22 and to chain sprocket 23. A flexible drive chain 24' connecting sprocket 23 and sprocket 6 by arm "85. Arm 85 is actuated by shaft 22 through racking crank 36 and links 87.

; In accordance with the invention mechanism uses the rotation of one crank to either manually charge the closing springs 52, '53, rack the circuit breaker into the cubicle or slowly'actuate the main movable primary arcing contacts 70, 71 for maintenance inspection. Y

When the selector lever 40 is arranged in the charge position shown in FIG. 3 handle 18 may be used to charge the stored energy closing springs 52, 53 or slowly actuate the arcing contacts 70, 7l'unde'r a given maintenance inspection procedure. This manually controlled contact actuation of the circuit breaker contacts is provided for checking the lead'relationship between the arcing contacts 70, 71 and the main contacts 106, 107, and for syn- 7 upon the ineffectiveness of springs 52, 53 and delivers or gear 15 causes rotation of pinion 16 inthesame manner as motor 17. The remainder of the sequence for w charging and discharging springs 52 and 53 is the same as above described under the motor energized sequence of this structure. r v I Manual release of the'stored energy springs 52 and 53 to close the arcing contacts 70 and 71 is accomplished by depressing mechanical closing button 90' which rotates prop latch '57 in the same manner as solenoid mechanism 60. Once released and the breaker contacts closed the springs 52 and 53 may be again recharged manually as previously described. 9 0

To rack the circuit breaker structure into its energized position in the cubicle the selector lever 40 is placed in the neutral position and the breakeris moved into the cubicle until the'slots in the racking cranks 82 engage with fixed pins '86attached to the sides of the cubicle. T o

. reach the racking position in the cubicle certain stops or interlocks in the cubicle are overcome in a predetermined I Once these interlocks are overcome in given manner. positions in the cubicle the breaker contacts can be closed chronizing contact engagement in all three phases of the circuit breaker (only one phase of the structure being shown. in the'drawings).

In order to accomplish the circuit breaker contact inspection when lever 40 is in the charge position shown in FIG. 3, handle 18 is rotated counterclockwise to fully charge the stored energy springs 52, 53. The check nuts 108 on maintenance closing bolts .109 are loosened and the bolts 109 screwed down approximately one-half inch. This adjustment will position bolts 109 in front of the stored energy springs 52, 53. Springs '52, '53 are then partially discharged against bolts 109 by actuating prop latch 57. This action renders the closing springs 52, 53 inoperative orinetfective even though they are in a biased position and moves pin 74 in slot 54 in link mechanism 54 a predetermined distance to the left. This action of pin 74 causes a predetermined clockwise rotation of eccentric 49 through connecting rod 50. The above described action is shown in FIG. 5.

Contact actuation is now controlled by the rotation of handle 18 counterclockwise which is rendered effective energy through shaft 19; Worm 20 and worm gear 21 into shaft 22 and to chain sprocket 23. A flexible drive chain 24 connecting sprocket 23and sprocket or gear 15 on shaft 14 causes rotation of pinion gear 16. The discharge of-springs 52 and 53 against bolts 109 causes spring 64 to bias the flexible teeth 63 of gear 45 into engagement with pinion gear 16. Thus, counterclockwise rotation of handle 18 causes clockwise rotation of gear -45 as shown in FIG. 1 and actuating of connecting rod 50 to the left causing clockwise rotation of bell crank 72 which lifts link 76 causing movement of toggle arms 79 and 80 to their overcenter position. This movement of toggle arms 79 and 80 causes a closing movement of the contact structure. As noted from the drawing, pin 74 is free to move in slot 54' provided for that purposein link mechanism 54 even through mechanism 54 is immobilized when the closing springsSZ. 53 are rendered inoperative.

The movable contact structure will be moved toward the closed position -bycounterclockwise rotation of handle 18 anduntil the breaker mechanism reaches its closed latched position its direction, of motion can be reversed by reversing the direction of handle rotation. When the contacts are actuated in contact opening direction the bias of spring 93 is accordingly, simultaneously reduced. Spring 93 opens the arcing. contacts whenever trip device 97 is actuated except that the biasing effect of spring 93 is dependent on the position of the arcing contacts, i.e., the closer to contact closed position of thecontacts the greater the bias of springr93. The actuation of spring 93 to open the contacts by triggering device 97 causes opening of the contacts independently of the movement of handle 18; When the latches 94 and 99 are released by triggering device 97, center 81'is not restrained as in normal closing operation, but is released to pivot about center 100. Thus, when closing energy is delivered to the togglelinkage through the closing cam 77, the toggle latch arm 99 rotates clockwise about the new center 100 perclaimed the selector 7 mitting the closing cam 77 to go through its complete cycle without moving link 102, and the breaker contacts therefore will not close. This action can take place during any part of the closing stroke, causing movable contact 70 to immediately return to the open position even though handle 18 is rotated counterclockwise to close the contacts. Further, closing the contacts with spring 93 has no effect on the movement of handle 13. In any position of the contact structure the movable contacts can be actuated to their fully open position by actuating the triggering trip device 97.

Although but one embodiment of the present invention has been. illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

Having now particularly described and ascertained the nature of my said invention and the manner in which it is to be performed, I declare that what I claim is:

1. A circuit breaker structure comprising in combination, a pair of cooperating relatively movable contacts, a closing device comprising a load means for closing said contacts upon bias thereof, an opening device comprising a load means for opening said contacts upon bias thereof, said closing means being connected to said opening means for biasing said opening means upon closure of said contacts, means for rendering said closing means ineffective when said closing means is in its biased position, and manual means rendered effective upon ineffectiveness of said closing means for actuating said contacts in contact opening and closing direction;

2. A circuit breaker structure comprising in combination, a pair of cooperating relatively movable contacts, a closing device comprising, spring, means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position, and manual means rendered effective upon ineffectiveness of said closing device for actuating said contacts in contact closing direction, said manual means biasing said opening device when actuated in contact closing direction.

3. A circuit breaker structure comprising in combination, a pair of cooperating relatively movable contacts, a closing device comprising, spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position, and manual means rendered effective upon ineffectiveness of said closing device for actuating said contacts when separated in contact opening and closing directions.

.4. A circuit breaker structure comprising in combination, a pair of cooperating relatively movable contacts, a closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device inefiective when said closing device is in its biased position, and manual means rendered effective upon ineffectiveness of said closing device for actuating at least one of said contacts when separated in contact opening and closing direction, said manual means biasing said opening device when actuated in contactclosing direction and reducing the bias of said opening device when actuated in contact opening direction.

5. A circuit breaker structure comprising in combina tion, a pair of cooperating relatively movable contacts, a

closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring, means for opening said contacts to a predetermined distance upon bias thereof, said closing device being connected to said' opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position, and manual means rendered effective upon ineffectiveness of said closing device for actuating at least one of said contacts when separated in contact opening and closing direction, said manual means biasing said opening device when actuated in contact closing direction and reducing the bias of said opening device when actuated in contact opening direction, said device for opening said contacts to said predetermined distance being effective in any position of said contacts.

6. A circuit breaker structure comprising in combination, a pair of cooperating relatively movable contacts, a closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position, and manual means rendered effective upon inefiectiveness of said closing device'for actuating at least one of said contacts when separated any distance between contact open and contact closed position in contact opening and closing direction.

7'. A circuit breaker structure comprising in combination, a pair of cooperating relatively movable contacts, a closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts upon bias thereof, said closing device being counectedto said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position, and dual purpose means for biasing said closing device and being rendered effective upon ineffectiveness of said closing device for actuating at least one of said contacts when separated in contact opening and closing directions.

8. A circuit breaker structure comprising in combination, a pair of cooperating relatively movable contacts, a closing, device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing is in its biased position, and dual purpose crank means for biasing said opening spring means and being rendered effective upon ineffectiveness of said closing device for actuating at least one of said contacts when separated in contact opening and closing direction, said crank means-biasing said opening device and closing said contacts when actuated in a common direction. 9. A circuit breaker structure comprising in combination, a'pair'of cooperating relatively movable contacts, a closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position, and dual purpose crank means effective upon ineffectiveness of said closing device for actuating at least one of said contacts when separated in contact opening and closing direction, said crank means biasing said opening device when actuated in contact closing direction and reducing the bias of said opening device when actuated in contact opening direction, said contact opening spring means being actuable independently of said crank means.

10. A circuit breaker structure for mounting in a cubicle comprising a frame, a pair of cooperating relatively movable arcing contacts mounted on said frame, a

closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts to a predetermined thereof, and dual purpose means for selectively actuating I said racking means and said contacts, said dual purpose means being rendered effective only upon ineffectiveness of said closing device for actuating said contacts when separated in opening and closing directions.

11. A circuit breaker structure for mounting in a cubicle comprising a frame, a pair of cooperating relatively movable arcing contacts mounted on said frame, a closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts to a predetermined distance upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position,a racking means mounted on said frame for cooperating with the cubicle for varying the position of said frame within the cubicle upon actuation thereof, and dual purpose means for selectively actuating said racking means and said contacts, said dual purpose means being rendered effective only upon ineffectiveness of said closing device for actuating said contacts when separated in opening and closing direction, said dual purpose means biasing said opening device when actuated in contact closing direction and re ducing the bias of said opening device when actuated in contact opening direction. I p

12. A circuit breaker structure for mounting in a cubicle comprising a frame, a pair of cooperating relatively movable arcing contacts mounted on said frame, a closing device comprising spring means for closing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts to a predetermined distance upon bias thereof, said closing device for varying the position of said frame within the cubicle upon actuation thereof, and dual purpose crank means being connected to said opening means for biasing said opening device upon closure of said contacts, means for rendering said closing device ineffective when said closing device is in its biased position, a racking means mounted on said frame for cooperating with the cubicle for selectively actuating said racking means and said contacts, said crank means being rendered effective only upon ineffectiveness of said closing device for actuating said contacts when separated in opening and closing direction, said crank means biasing said opening device when actuated in contact closing direction and reducing the bias: of

2 said opening device when actuated in contact opening di- 15 rectiori, said spring means for opening said contacts to said predetermined distance being effective in any position of said contacts.

, 13. A circuit breaker structure for mounting in a cubicle comprising a frame, a pair of cooperating relatively movablearcing contacts mounted on said frame, a closing device comprising spring means forclosing said contacts upon bias thereof, an opening device comprising spring means for opening said contacts to a predetermined distance upon bias thereof, said closing device being connected to said opening device for biasing said opening device upon closure of said contacts, means for render! ing said closing device ineffective when said closing device is in its biased position, a racking means mounted on said frame for cooperating with the cubicle for varying the position of said frame Within the cubicle upon actua tion thereof, a dual purpose driving means for actuating said racking means and said contacts upon movement thereof, and crank means for selectively connecting said driving means to said racking means and contacts for actuation thereof, said crank means being rendered effec tive'only upon ineffectiveness of said closing device for actuating said contacts when separated in opening and closing direction, said crank means biasing said opening device when actuated in contact closingdirection and reducing the bias of said opening device when actuated in contact opening direction, said spring means for opening said contacts to said predetermined distance being effective in any position of said contacts. 7

References Cited in the file of this patent UNITED STATES PATENTS Hay June 28, 196Q