US3183332A - Circuit breaker closing mechanisms - Google Patents

Description

May 11, 1965 R. E. FRINK ETAL 3,183,332

I CIRCUIT BREAKER CLOSING MECHANISMS Filed Aug. 9, 1962 7 Sheets-Sheet 1 INVENTQRS Russell E. Frank 8 Paul Olsson ATTORNEY May 11, 1965 R. E. FRINK ETAL CIRCUIT BREAKER CLOSING MECHANISMS Filed Aug. 9, 1962 7 Sheets-Sheet 2 May 11, 1965 R. E. FRINK EI'AL 3,183,332

CIRCUIT BREAKER CLOSING MECHANISMS Filed Aug. 9, 1962 7 Sheets-Sheet 3 May 1965 R. E. FRINK ETAL CIRCUIT BREAKER CLOSING MECHANISMS 7 Sheets-Sheet 4 Filed Aug. 9, 1962 mm mm May 11, 1965 R 5 mm ETAL 3,183,332

CIRCUIT BREAKER CLOSING MECHANISMS Filed Aug. 9, 1962 7 Sheets-Sheet 5 May 11, 1965 R. E. FRINK ETAL 3,183,332

CIRCUIT BREAKER CLOSING MECHANISMS Filed Aug. 9, 1962 7 Sheets-Sheet 6 May 11, FRINK T CIRCUIT BREAKER CLOSING MECHANISMS Filed Aug. 9, 1962 '7 Sheets-Sheet 7 United States Patent CHRCUET BREAKER CLGSING MECHANZSRIS Russell E. Frink, Forest Hilts, and Paul ()lssen, Penn Townshir Allegheny County, Pa., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Aug. 9, 1962, Ser. No. 215,854 19 Claims. (Cl. 20i)153) This invention relates, generally, to closing mechanisms for circuit breakers and, more particularly, to mechanisms of a type in which energy for closing a circuit breaker is stored in a spring.

Numerous closing mechanisms of the spring storedenergy type have been constructed heretofore. However, the prior mechanisms have been complicated in structure and operation. Furthermore, they have not been suitable for operating circuit breakers of a relatively large size.

An object of this invention is to provide a stored-energy closing mechanism which shall be simple in construction and efiicient in operation and which may be economically manufactured and installed.

A more specific object of the invention is to provide a stored-energy closing mechanism which is trip-free.

Another object of the invention is to provide a closing mechanism in which energy may be stored in a spring by electrically operated means or by manually operated means.

A further object of the invention is to provide for reducing shock on the mechanism during both closing and opening of the breaker.

Other objects of the invention will be explained fully hereinafter or will be apparent to those skilled in the art.

In accordance with one embodiment of the invention, energy is stored in a spring by means of a crankshaft which is driven by a motor through a ratchet and pawl device. When the stored energy is released, the crankshaft drives a cam, secured to the shaft, to extend a toggle system which drives a trip-free shaft to close the contact members of the circuit breaker. The toggle system includes only two links, one of which is always under tension and is attached directly to the tripping latch assembly to provide trip-free operation. A spring and dashpot assembl reduces shock on the mechanism during both closing and opening of the breaker.

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:

FIGURE 1 is a view, in front elevation, of a circuit breaker closing mechanism embodying the principal features of the invention;

FIG. 2 is a view, in top plan, of the mechanism shown in FIG. 1;

PEG. 3 is a View, partly in left side elevation and partly in section, of the mechanism;

FIG. 4 is a view, in right side elevation, of the mechanism;

FIG. 5 is a view, partly in section and partly in elevation, of a portion of the mechanism shown in FIG. 1;

FIGS. 6 to 9, inclusive, are detail views showing different operating positions of parts of the closing mechanism; and

FIG. 10 is a View, partly in section and partly in elevation, of an accelerating spring and dashpot assembly utilized in conjunction with the mechanism.

Referring to the drawings, the spring stored-energy mechanism shown therein is suitable for use with a relatively high voltage magnetic air circuit breaker, such as the type DH circuit breaker manufactured by the Westinghouse Electric Corporation. However, with slight modifiice cation, the mechanism can be applied to circuit breakers of other types.

As shown, the mechanism is supported by a frame 11 which may be attached to the frame of the circuit breaker (not shown). Generally, the mechanism comprises a trip-free shaft 12, a closing spring 13, a crankshaft 14, a ratchet mechanism 15, a motor 16, a toggle linkage 17, a cam 13, and an accelerating spring and dashpot assembly 19. The trip-free shaft 12 is rotatably mounted in bearings 21 disposed in the frame 11. An operating lever 22 is secured to each end of the shaft 12. A third operating lever 23 is secured to the middle portion of the shaft 12. Operating members 24 are pivotally attached to the operating levers by means of pins 25. The operating members 24 are attached to the movable contact members (not shown) of the circuit breaker to actuate the contact memhere. The operating levers 22 each have a lower arm 26 utilized for a purpose which will be described hereinafter.

As shown most clearly in FIG. 4, one end of the closing spring 13 rests in a spring seat 27 provided in the frame 11. The other end of the spring 13 engages a spring retainer 28 which is retained on a rod 29 by means of a pin 31. The rear end of the rod 29 is supported by a link 32, one end of which is attached to the rod 29 by the pin 31 and the other end of which is pivotally attached to the frame of the circuit breaker (not shown). The other end of the rod 29 is threaded into a block 33, thereby permitting the effective length of the rod to be adjusted to vary the amount which the spring 13 is compressed between the spring seat 27 and the retainer 28. The block 33 is attached to a crank pin 34 which is carried by a crank lever 35 attached to one end of the crankshaft 14. As shown in FIG. 4, the spring 13 is in its most relaxed position. When the crank lever is rotated from the position shown, the spring 13 is fully charged.

The ratchet mechanism 15 comprises a ratchet wheel 36, an actuator 37, a pawl carried by the actuator 37, and an additional pawl 3% pivotally mounted in the frame 11 by means of a pin 41. The ratchet whee 36 is secured to the end of the shaft 14 opposite the crank lever 35. The wheel 36 has a plurality of teeth disposed around a portion of its periphery. The actuator 37 pivots on the shaft 14 and is biased toward an eccentric 43 by a tension spring 44. A roller 45, carried by the actuator 37, engages the eccentric 43. The pawl 38 is biased toward the ratchet wheel 36 by means of a torsion spring 46. The pawl 39 is also biased toward the ratchet wheel 36 by means of a torsion spring 47.

The motor lid drives a shaft 48 through spur gears and 51. The eccentric 43 is secured to the shaft 45 Thus, when the motor 16 runs, the ratchet wheel 36 is advanced one tooth for each revolution of the shaft 43 in the clockwise direction, as viewed in PEG. 3, by means of the actuator 37 and the pawl 38. The pawl 39 prevents the wheel 35 from rotating backwards between strokes of the actuator 37. The last tooth on the ratchet wheel carries the crank lever 35 just over center in the spring charged position, and the force of the main spring 13 brings a roller 52, carried by the crank lever 35, against a closing latch 53 as shown in FIG. 7. In this position, there are no more teeth on the ratchet whee for the pawl 38 to engage and the motor L6 runs free until it is shutoff.

The toggle linkage 17 comprises links which are pivotally attached to the operating lever 23 by means of a pin 55, and a link 56, one end of which is pivotally attached to the links 54 by means of a pin 57. Two rollers 58 are also mounted on the pin 57.

As shown most clearly in FIGS. 5 to 9, the other end of the link 56 is pivotally attached to a tripping latch assembly 59. The assembly 5h comprises a cam 61 pivoted on a pin 62, a rocker arm 63 pivoted on a pin 64, and :a trip latch 65 pivoted on a pin 66. The one end of the link 56 is pivotally attached to the cam 61 by means of a pin 67. The rocker :arm 63 is biased toward the cam 61 by a torsion spring (not shown). The latch 65 is biased toward the rocker arm 63 by a torsion spring (not shown). The toggle linkage 17 is so constructed that the link 56 is under tension when the rollers 58 are engaged by the cam 18. A tension spring 711 is stretched between the pin 57 of the toggle linkage and the frame 11.

As previously stated, the cam 13 is secured to the crankshaft -14. The crank lever 35 and the ratchet wheel 36 are also secured to the crankshaft 14.

As shown more clearly in FIG. 10, each accelerating spring and dashpot assembly. 19, of which two are provided, comprises a shaft 72, a spring retainer 73, la cylinder 74, a piston 75 and accelerating springs 76 and 77. A rod end is secured to one end of the shaft 72. The rod end 78 is pivotally attached to the lower portion 26 of one of the operating levers 22 which, as previously explained, are secured to the shaft 12. The rod end 73 is attached to the lever portion 26 by .a pin 79. One end of the cylinder 74 is pivotally attached to a bracket 81 by means of a pin 82. The bracket 81 is attached to the frame 11. The piston 75 is attached to one end of the shaft 72 by a pin 83. An opening 84 extends through the piston '75. The spring retainer '73 is attached to the shaft 72 by a pin 85. The spring retainer 73 is cast with a key shaped opening which cooperates with the pin so that rotating the retainer screws the shaft into or out of the rod end 78 to adjust the breaker contact open position. The spring 77 is disposed between the retainer 76 and the cylinder 74. One end of the spring 76 engages the retainer '75 and the other end surrounds the cylinder 74, and in the partially closed position engages lugs 68 around the periphery of the cylinder to. provide high initial opening acceleration.

As shown, openings 96 are provided in one end of the cylinder 74. These openings are closed by valves 97 which are biased to the closed position by relatively light springs 69.

The operation of the mechanism may be best understood by referring to FIGS. to 9, inclusive. Assuming that the breaker is open and the spring '13 discharged, the crank lever 35 is as shown in FIG. 6, the cam 16, the operating lever 23, the tripping latch assembly 59 and a spring-biased latch 86 are as shown in FIG. 9. The latch 86 pivots on a pin 87 and is biased toward the crankshaft 1-4 by a spring 83. When the motor 16 is energized, it operates the ratchet mechanism to drive the crankshaft 14, thereby charging the spring 13. As previously explained, When the spring is charged, the roller 52, carried by the crank lever 35, engages the closing latch 53 as shown in FIG. 7. At this time, the cam 18, the lever :23 and the tripping latch assembly 59 are as shown in FIG. 8, having been reset by the spring 71. The pressure of the roller 52 against the sloping surface of the latch 53 biases the latch in a counterclockwise direction against a roller 96 carried by a closing trigger 91. The trigger 9 1. is biased in a counterclockwise direction about its pivot 92 by a spring 93. Lifting the trigger 91 releases the latch 5-3 and the closing spring 13 rotates the crank lever and the cam 18 in -a counterclockwise direction to close the breaker as shown in FIG. 5. In this position, the toggle link-v age 17 is fully extended.

During its upward movement, the roller 58 has pushed the latch 86 to the left and the latch drops under the tension, thereby tending to rotate the cam 61 in a counterclockwise direction. Lifting the trip latch 65 releases the cam 61 so that the roller 58 runs out on the cam 13, as shown in FIG. 9, or off of the latch 36 if the spring 13 is recharged, thereby permitting the linkage to reset as shown in FIG. 8. It will be understood that the trip latch 65 land the closing latch 91 may be operated in any manner well known in the art to control the tripping and the closing of the circuit breaker.

As previously explained, the entire linkage system is so constructed that at all points of the closing stroke, the link 56 is under tension. Thus, if the trip latch 65 is released, the breaker will open irrespective of the position of the cam 18. In this manner the breaker is made trip-free at all times. The toggle linkage is permitted to collapse to the position shown in FIG. 9 whenever the trip latch 65 israised to release the cam 61. It will be understood that the cam 18 and the linkage mechanism may be so constructed that the torces applied to the linkage match the forces required by the circuit breaker during the closing operation. As shown, the cam has an increasing lobe portion which applies pressure on the links 54 to close the breaker.

The satisfactory operation of a relatively high voltage circuit breaker with one pair of contacts per pole requires extremely high contact welocity during opening of the breaker. Tests on a breaker of one type have shown that a travel of seven inches is required in the first cycle after the contact members separate. In order to accomplish this, an initial accelerating torque of 30,000 inch pounds is required. The function of the accelerating spring and dashpot assembly 19 is to provide the required accelerating torque during opening and to reduce shock on the mechanism during both opening and closing of the breaker contact members. 7

As previously explained, two of the a ssemblies 19 are provided, one being attached to each one of the operating levers 22. The operation of the assembly :19 will be best understood by referring to FIG. 10. When the breaker is closed, the pin 79 moves the shaft or rod 72 and the piston 75 to the right. 7 This compresses the springs 76 and 77. It will be understood that the closing spring 13 must have suflicient strength to compress the springs 76 and 77 while the contact members of the circuit breaker are being closed. When the piston 75 passes a porthole in the center of the cylinder 74, the trapped air attempts to flow through holes 96 in the rear end of the cylinder 74. However, the air closes valves 97 more tightly, thereby compressing the air. The compressed air must exhaust through the leak hole 84 in the piston 75. This cushions the closing shock. A sealing member 98 c0mpressed by a spring 99 around the rod 72 prevents air from escaping around the piston rod.

During opening of the breaker, the accelerating spring 76 and 77 rotate the lever 26 clockwise and the piston 75 moves to the left. The suction of the piston opens the valves 97 so that air can enter the cylinder behind the piston. When the piston passes the port 95, air is trapped to the left of the piston, compressed and permitted to escape through the leak hole 84. This cushions the latter part of the opening stroke and prevents excessive rebound of the contact members of the circuit breaker. Thus, shock on the mechanism is reduced during both closing and opening of the circuit breaker.

As previously explained, the operation of the' circuit breaker during closing andopening may be controlled in a manner well known in the art. Furthermore, the

7 operation of the motor 16 may be controlled by limit roller in the brea ker'closed position so that the crankshaft 14 and the cam 18 can be rotated counterclockwise to recharge the spring 13 while the breaker remains closed. As previously explained, the spring 13 is charged by energizing the motor 1-6 to operate the ratchet mechanism 15. V V e In the position shown in- FIG. 5, the link 56 is under switches of a type well known in the art; The ratchet mechanism may be operated manually to charge the spring 13 if it becomes necessary to do so. 7

From the foregoing description, it is apparent that the invention provides a spring "stored-energy mechanism which is suitable for operating a circuit breaker. The

circuit breaker is trip free at all times during the closing operation. The mechanism is simple in construction and ei'ficient in operation.

Since numerous changes may be made in the abovedescribed construction and different embodiments of the invention may be made Without departing from the spirit and scope thereof, it is intended that all the matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. A stored-energy mechanism comprising a frame, a trip-free shaft rotatably mounted in the frame, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, cam means driven by the crankshaft when said closing latch means is released to release said spring, tripping latch means, toggle means connected between the tripping latch means and the trip-free shaft, and said toggle means being extended by said cam means to rotate the trip-free shaft when the closing latch means is released to release the energy stored in said spring.

2. A stored-energy mechanism comprising a frame, a trip-free shaft rotatably mounted in the frame, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, an operating lever secured to the tripfree shaft, tripping latch means, toggle means having one link connected to the trip-free shaft and another link connected to the tripping latch means, and cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft when the closing latch means is released to release the energy stored in said sprin 3. A stored-energy mechanism comprising a frame, a trip-free shaft rotatably mounted in the frame, a closing spring, a crankshaft rotatably rnounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means having one link connected to the tripfree shaft and another link connected to the tripping latch means, cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft when the closing latch means is released to release the energy stored in said spring, and said tripping latch means being releasable to prevent the cam means from rotating the trip-free shaft.

4. A stored-energy mechanism comprising a frame, a trip-free shaft rotatably mounted in the frame, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closlatch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means having one link connected to the trip-free shaft and another link connected to the tripping latch means, cam means secured to the crankshaft to extend the toggle means to rotate the trip-free shaft when the closing latch means is released, and said tripping latch means being releasable to collapse the toggle means.

5. A stored-energy mechanism comprising a frame, a trip-free shaft rotatably mounted in the frame, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, an operating lever secured to the trip-free shaft, tripping latch means, toggle means having a first link and a second link pivotally connected together, one end of the first link being pivotally attached to said operating lever, one end of the second link being pivotally attached to the tripping latch means, cam means secured to the crankshaft, and said cam means being driven by the spring to extend the toggle means to rotate the tripfree shaft when the closing latch means is released.

6. A stored-energy mechanism comprising a frame, a trip-free shaft rotatably mounted in the frame, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, an operating lever secured to the trip-free shaft, tripping latch means, toggle means having a. first link and second link pivotally connected togethcr, one end of the first link being pivotally attached to said operating lever, one end of the second link being pivotally attached to the tripping latch means, cam means secured to the crankshaft, said cam means being driven by the spring to extend the toggle means to rotate the tripfree shaft when the closing latch means is released, and said tripping latch means being releasable to collapse said toggle means.

7. A stored-energy mechanism comprising a frame, a trip-free shaft rotatably mounted in the frame, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, an operating lever secured to the trip-free shaft, tripping latch means, toggle means having a first link and a second link pivotally connected together, one end of the first link being pivotally attached to said operating lever, one end of the second link being pivotally attached to the tripping latch means, cam means secured to the crankshaft, said cam means being driven by the spring to extend the toggle means to rotate the trip-free shaft when the closing latch means is released, said second toggle link being under tension during extension of the toggle means, and said tripping latch means being releasable to release said tension and collapse the toggle means.

8. In a stored-energy mechanism for actuating contact members of a circuit breaker, in combination, a frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating means for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, a ratchet wheel secured to the crankshaft, a pivoted actuator for driving the ratchet wheel and the crankshaft to charge the spring, a motor for oscillating the actuator, closing latch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, and cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft and to close the contact members of said circuit breaker when the closing latch means is released to release the energy stored in said spring.

9. in a stored-energy mechanism for actuating contact members of a circuit breaker, in combination, a frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating means for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, a ratchet Wheel secured to the crankshaft, a pivoted actuator for driving the ratchet Wheel and the crankshaft to charge the spring, a motor for oscillating the actuator, closing latch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft and to close the contact members of said circuit breaker when the closing latch means is released to release the energy stored in said spring, and said tripping latch means being releasable to prevent the cam means from rotating the trip-free shaft.

10. a stored-energy mechanism for actuating contact members of a circuit breaker, in combination, a frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating cans for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, a ratchet wheel secured to the crankshaft, a pivoted actuator for driving the ratchet wheel and the crankshaft to charge the spring, a motor for oscillating the actuator, closing latch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft and to close the contact members of said circuit breaker when the closing latch means is released to release the energy stored in said spring, and a spring-biased latch for retaining the toggle means in its extended position.

11. In a stored-energy mechanism for actuating contact members of a circuit breaker, in combination, a frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating means for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, a ratchet wheel secured to the crankshaft, a pivoted actuator for driving the ratchet wheel and the crankshaft to charge the spring, a motor for oscillating the actuator, closing latch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft and to close the contact members of said circuit breaker when the closing latch means is released to release the energy stored in said spring, a spring-biased latch for retaining the toggle means in the extended position, and said tripping latch means being re leasable to collapse the toggle means.

12. In a stored-energy mechanism for actuating contact members of a circuit breaker, in combination, a frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating means for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, a ratchet wheel secured to the crankshaft, a pivoted actuator for driving the ratchet wheel and the crankshaft to charge the spring, a motor for oscillating the actuator, closing latch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft and to close the contact members of said circuit breaker when the closing latch means is released to release the energy stored in said spring, a spring-biased latch engaging said toggle means to retain it in its extended position, and said tripping latch means being releasable to collapse the toggle means irrespective of the cam means and the spring-biased latch.

13. In a stored-energy mechanism for actuating contact members of a circuit breaker, in combinatioma frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating means for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, tripping latch means,

toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, cam

means driven by thecrankshaft to extend the toggle means to rotate the trip-free shaft and close the contact members of the breaker when the closing latch means is released to release the energy stored in the spring, accelerating spring means charged during closing of the contact members, said tripping latch means being releasable to collapse the toggle means and permit the accelerating spring means to open the contact members, and dashpot means connected to at least one of said operating levers to reduce shock on the mechanism during opening of the contact members.

14. In a stored-energy mechanism for actuating contact members of a circuit breaker, in combination, a frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating means for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, tripping latch means, toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft and close the contact members of the breaker when the closing latch means is released to release the energy stored in the spring, accelerating spring means charged during closing of the contact members, said tripping latch means being releasable to collapse the toggle means and permit the accelerating spring means to open the contact members, and dashpot means connected to the trip-free shaft to reduce shock on the mechanism during closing of the contact members and during opening of the contact members.

15. In a stored-energy mechanism for actuating contact members of a circuit breaker, in combination, a frame, a trip-free shaft rotatably mounted in the frame, a plurality of operating levers secured to the shaft, operating means for connecting said levers to the breaker contact members, a closing spring, a crankshaft rotatably mounted in the frame, means for driving the crankshaft to charge the spring, closing latch means for releasably retaining the spring in the charged condition, tripping latch means,

toggle means connected between the tripping latch means and one of the operating levers on the trip-free shaft, cam means driven by the crankshaft to extend the toggle means to rotate the trip-free shaft and close the contact members of the breaker when the closing latch means is released to release the energy stored in the spring, accelerating spring means carried by a shaft having one end pivotally attached to one of the operating levers, said accelerating spring means being'charged during closing of the contact members, said tripping latch means being releasable to collapse the toggle means and permit the accelerating spring means to open the contact members, and dashpot means connected to the other end of said shaft to reduce shock on the mechanism during closing of the contact members and during opening of the contact members.

16. In a circuit breaker closing mechanism, a cam rotatable to close the breaker, said cam having an increasing lobe portion, a roller disposed to engage and follow the cam, a toggle linkage carrying the roller and including a tension link and a compression link pivotally connected together, said cam being disposed adjacent to said linkage with the compressive force in said compression link biasing the roller toward the increasing lobe portion of the cam, and a releasable restraining link for preventing motion of said roller in the latter direction.

17. A circuit breaker closing mechanism, comprising a cam rotatable to close the breaker, said cam having an increasing lobe portion, a roller disposed to engage and follow the cam, a toggle linkage carrying the roller and including a tension link and a compression link pivotally connected together, said cam being disposed adjacent to said linkage with the compressive force in said compression link biasing the roller toward the increasing lobe portion of the cam, said tension link acting as a releasable restraining link for preventingrnotion of said roller in the latter direction, and said restraining link being under tension during the closing operation.

13. A circuit'breaker closing mechanism, comprising a cam rotatable to close the breaker, said cam having an increasing lobe portion, a roller disposed to engage and follow the cam, a toggle linkage carrying the roller and including a tension link and a compression link pivotally connected together, said cam being disposed adjacent to said linkage with the'compressive force in said compression link biasing the roller toward the increasing lobe portion of the cam, said tension link acting as a releasable restraining link for preventing motion of said roller in the latter direction, said restraining link being under tension during the closing operation, and trip means for releasing said restraining link to permit motion of said roller toward said increasing lobe portion of said cam.

19. In a circuit breaker closing mechanism, a cam rotatable to close the breaker, said cam having an increasing lobe portion, means for rotating the earn, a roller disposed to engage and follow the cam, a toggle linkage carrying the roller, said linkage comprising a compression link and a tension link, said cam being disposed adjacent

Claims (1)

1. A STORED-ENERGY MECHANISM COMPRISING A FRAME, A TRIP-FREE SHAFT ROTATABLY MOUNTED IN THE FRAME, A CLOSING SPRING, A CRANKSHAFT ROTATABLY MOUNTED IN THE FRAME, MEANS FOR DRIVING THE CRANKSHAFT TO CHARGE THE SPRING, CLOSING LATCH MEANS FOR RELEASABLY RETAINING THE SPRING IN THE CHARGED CONDITION, CAM MEANS DRIVEN BY THE CRANKSHAFT WHEN SAID CLOSING LATCH MEANS IS RELEASED TO RELEASE SAID SPRING, TRIPPING LATCH MEANS, TOGGLE MEANS CONNECTED BETWEEN THE TRIPPING LATCH MEANS AND THE TRIP-FREE SHAFT, AND SAID TOGGLE MEANS BEING EXTENDED BY SAID CAM MEANS TO ROTATE THE TRIP-FREE SHAFT WHEN THE CLOSING LATCH MEANS IS RELEASED TO RELEASE THE ENERGY STORED IN SAID SPRING.

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