US2756306A - Circuit breaker operating mechanism - Google Patents

Description

y 4, 1956 R. J. BASKERVILLE CIRCUIT BREAKER OPERATING MECHANISM 2 Sheets-Sheet 1 Filed Oct. 1, 1953 Bask ville,

y 24, 1956 R- J. BASKERVILLE CIRCUIT BREAKER OPERATING MECHANISM 2 Sheets-Sheet 2 Filed Oct. 1, 1953 Inventor: 'RaPEJJ. Baskerville,

His b'tor'neg.

United States Patent CIRCUIT BREAKER OPERATING MECHANISM Ralph J. Baskerville, Drexel Hill, Pa., assignor to General Electric Company, a corporation of New York Application October 1, 1953, Serial'No. 383,567

15 Claims. (Cl. 200-16?) This invention relates to an operating mechanism for a circuit breaker and, more particularly, to an operating mechanism which depends for its proper operation upon the ability of certain parts of the mechanism to rapidly reverse their direction of movement.

In certain types of circuit breakers having an operating handle manually operable in one direction to effect closing of the breaker contacts, proper operation of the breaker is possible only if the operating handle is free to move in a reverse direction in response to opening of the breaker contacts. An example of such a circuit breaker is a breaker of the automatically reclosing type such as is disclosed and claimed in Patent No. 2,633,514, McCurry et all, which is assigned tothe assignee of the present invention. For example, in the circuit breaker disclosed in the McCurry et al. patentthere is provided a manually operable handle which is automatically movable by the circuit breaker to an open position in response to the breaker contacts being locked open' due to a predetermined electrical fault condition. Now in the event that this fault condition has not cleared after the handle has been locked open, and the handle is subsequently manually operated, as by a hook stick, to effect reclosing of the breaker contacts, it is highly desirable that the circuit breaker relockout immediately in response to a single time-delayed opening of the breaker contacts. Although the aforementioned circuit recloser is capable of this desirable relockout movement, such movement can be defeated unless the operator, after manually lifting the handle with the hook stick so as to reclose the breaker contacts, immediately removes his hook stick from the eye of the handle, i. e., at least before-the expiration of the sing e time-delayed reopening period, thereby to permit the handle to move freely downwardly again coincident with the relockout movement. If such downward movement of the handle is'prevented, the desired relockout of the recloser would also be prevented. Accordingly, it will be observed that proper operation of such'a breaker is not assured unless theoperator is prevent'edfrom holding the handle in the closed, or reset, position for a period of time exceeding the time-delayed reopening period.

It is therefore an object of my invention'to provide for a circuit breaker anew and improved operating handle construction which acts to prevent the possibility of improper operation of the breaker due to the-handle being held in a closed or reset position for an excessive period of time.

It is a further object of my invention to provide a means for automatically uncoupling the movable contact structure of a circuit breaker from operative relationship with a manually-controlled operating part after movement of said part has caused said contact structure to move to closed position.

It is a further object of my invention'to provide in an operating mechanism having a handle which is manuallyoperable through a hook stick, means whereby the hook stick is automatically rendered'incapable of holding the 2, handle in closed position after a predetermined closing movement of the handle.

In carrying out my invention in one form, there is provided, for producing movement oftlie movable contact structure of a circuit breaker, an operating mechanism comprising an operating shaft, a cooperating handle structure mounted on said shaft and having a portion which receives a hook stick for effecting operation of said shaft, and means for automatically uncoupling said hook stick from force-transmitting relationship with said shaft after predetermined movement of said operating mechanism.

Further objects and advantages of my invention will become apparent as the following description proceeds, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part ofthis specification.

For a better understanding of my invention, reference may be had to the accompanying drawing in which Fig. 1 is a side view showing, in open position, one embodiment of a handle constructed in accordance with the present invention; Fig. 2 is a side view of the handle of Fig. 1 shown as it is moved into closedposition" and at the instant that the hook stick is released from force-transmitting relationship with the handle; Fig. 3 is a sectional view taken along the line 33 of Fig. 2; Fig. 4 is a side view of a second form of handle embodying the present invention, the bandle being shown in closed position; and Fig. 5 is a side view of the handle of Fig. 4 shown in open position. Figs. 6 and 7 are side views of still anotherform of handle constructed in accordance with the present invention.

While the present invention is particularly applicable to circuit breakers of the type shown in the aforementioned McCurry et' al. patent, it is to be understood that the inventionhas application to other types of manuallyoperable circuit breakers wherein proper operation of the circuit breaker is adversely affected by an operators holding the operating handle of the breaker in closed or reset position for an excessive period of time after he has closed the breaker.

In Figs. 1-3 there is shown a manually-controlled operating mechanism for a circuit breaker which may be of the reclosing type shown in the McCurryet al. patent. Manual closing of the breaker contacts (not shown) may be efiected, as-more fully described-in the McCurry et al. patent, by moving the arm 13 counterclockwise about the axis of operating shaft. 14 from the open position of Fig. 1 to the closed or reset position of Fig. 2. As seen in Fig. 3, the shaft 14 is suitably'journaled at 15 in frame structure disposed on the usual circuit breaker housing. The shaft 14 is fixedly related to-the arm 13 so'that rotationof the shaft 14 willeifect operative movement of the arm-13.

In order to operatively rotate the" shaft 14 there is provided an improved handle structure 17 which cooperates with the adjacent frame structure 16 in a novel manner which will become apparent as the description proceeds. The handle structure 17 comprises a handle member 18 suitably fixed with respect to the shaft 14, as by means of abolt 19. Thehandlemember 18 terminates at its outer end in an apertured generally ringshaped portion 20 which is adapted to receive a conventional hook stick indicated generally at 21, which isused to effect operative movement of the handle member 18.

The apertured portion 20- hasan. open upper side, but for releasably retaining the hook stickwithin the apertured portion and for transmittingthe lifting force of the hook stick to the handle 18, there is provided a releasable coupling or retaining structure 221 This retaining structure 22 is carried by the handle 18 and comprises a levertype clasp 23 and a retaining latch 24'. As seen in Fig. 3, the inner end of the lever or" clasp 23 is bifurcated to constitute a clevis which is pivotally'mountedon the hendle 18 bya pivot pin 25 which extends through the handle 18 and into registering apertures formed in the clevis. Pivot .pin 25 is suitably anchored into one arm of the clasp clevis by the shoulder of the reduced portion 40 on one side of the arm and the cotter pin 41 on the other side. Washers 42 on either side of the handle 18 provide for proper alignment of these associated parts. The clasp 23 is spring-biasedin clockwise direction about its pivot pin 25 so. as to normally span the open side of the apertured portion of the handle. The latch 24, which is pivotally supported on the handle 18 by means of a shouldered pin 26 riveted thereto is biased in a counterclockwise direction about its pivot pin 26 and is formed with a notch 27 which normally receives the catch 28 projecting from the clasp 23, as shown in Fig. 1. For biasing the latch and'the clasp in the proper directions and into cooperating latched relationship, there is utilized a common torsionspring 29, encircling the pin and hearing at its opposite ends against the latch and the clasp respectively. Thus, when the clasp 23 is latched, an operators upward thrust of the hook stick 21 is normally resisted by the latched clasp so that the end of the handle 18 may act as a closed ring.

For disengaging the latch from the clasp at a predetermined point in the upward or closing stroke of the handle 18, there is provided a disengaging screw 30 which is adjustably mounted on the frame structure 16, as by threading the screw into a suitably threaded aperture in the frame structure 16. For locking the screw in the movement of the handle. As this movement takes place,

coupling or retaining structure 22 serves to retain the hook stick in the open-sided aperture portion 20 and to transmit the lifting action of the hook stick to the handle until the latch 24 engages the screw 30. When this engagement occurs, the screw 30 cams the latch 24 clockwise about its pivot and away from the catch 28 of the clasp 23. This movement unlatches the latch and the clasp, as a result of which the clasp 23 yields to the thrust of the hook stick so that the latter slips through the now open side of the aperture and automatically frees itself'from effective force-transmitting relationship with the handle. Thus, it will be understood that the solid lines of Fig. 2 indicate the point at which the upwardly moving hook stick 21 is about to free itself from the handle 18 by rotating the clasp 23 against its light resetting spring 29 to its further position shown by the dotted lines, after which an operator would draw the hook stick away entirely. The clasp 23 meanwhile would have snapped back to its normally latched bridging position across the open end of the'handle 18. Now if the above described breaker closing action should take place in the McCurry et al. type of circuit breaker when there is a fault condition present on the. line, proper operation of the breaker, i. e. lock-out, would be possible only if the handle were permitted to move downwardly from the closed position of Fig. 2 after a very short time delay. Where the handle is of the conventional ring type shown in the McCurry patent, it will be apparent that the hook stick, if not immediately withdrawn from the eye of the handle, would interfere with this downward movement and adversely affect the circuit breaker operation by preventing the desired lock-out. In the present device, however, the clasp 23 is unlatched when the breakeris closed so that even though the hook stick is held by the operator in the upper position, the stick is now disengaged from force-transmitting relationship with the handle and,

thus, can ofier no effective resistance to a following downward or lock-out movement of the handle in the event that an opening operation immediately ensues.

As more fully explained in the McCurry et al. patent,

if it is desired to manually open the breaker from the I normally closed position indicated by Fig. 2, it is necessary merely to insert the hook stick in the ring-shaped apertured portion 20 of the handle 13 and then to pull the hook stick downwardly so as to pivot the handle into the position of Fig. l.

A second form of the present invention is shown in Figs. 4 and 5 wherein there is provided a handle 50 generally corresponding to the handle 18 of Fig. 1. This handle 50 is pivoted on an operating shaft at 51 and terminates at its outer end in an open-sided apertured portion 52 which is generally ring-shaped and which is adapted to receive a hook stick which is shown generally at 53. In a manner corresponding to that described with respect to Figs. 1-3, the hook stick is adapted to engage in the apertured portion and to move the handle 50 and the internal contact operating arm 54 between the open position of Fig. 5 and the closed position of Fig. 4. The book stick 53 as it is moved toward closed position is releasably retained in the apertured portion 52 by coupling or retaining structure comprising an upper arm 55 integral with the handle. This retaining structure, or arm 55, transmits the closing, or lifting, force of the hook stick 53 to the handle 50 until the hook stick is cammed away from handle 50, as will appear more clearly hereinafter.

For camming the hook stick 53out on engagement with the handle 50 at a predetermined point in the closing stroke of the handle, there is provided adjustable release means comprising a cam plate 59 having a cam surface 6%, the cam plate being adjustably mounted on the adjacent frame structure 61. More particularly, the cam plate 59 is pivotally mounted closely adjacent the handle 50 on a shaft 62 fixedly supported in the frame structure 61 and is biased in counterclockwise direction by a suitable spring 63. An adjusting screw 64, threaded in the enclosing structure 61 bears against the upper end of the cam plate 59 so as to hold the cam plate in a predetermined desired position. A lock nut 65 is used to lock the adjusting screw in the desired position of adjustment.

'The operation of this form of the invention is as follows: When its is desired to close the circuit breaker by manually moving the handle 50 from the open position of Fig. 5 to the closed position of Fig. 4, the hook stick 53 is first inserted in the apertured portion 52 of the handle, after which the hook stick is lifted to effect counterclockwise pivotal movement of the handle. As the hook stick is lifted it slidably engages the cam surface 60, but the lifting action of the hook stick continues to be transmitted to the handle through the retaining structure or arm 55 until the outer edge 56 of the retaining structure moves into substantial alignment with the cam surface 60. When this aligned condition occurs, the retaining structure or arm 55 is no longer effective to retain the hook stick in force-transmitting relationship to the handle, as a result of which the disconnected hook stick, under the influence of the operators lifting action, continues moving along the cam surface 60 into the position closed position is effectively prevented.

In Figs. 6 and 7 of the drawing there is shown still another embodiment of the invention. In this embodiment of the invention, the releasable coupling is disposed between the operating shaft and the handle instead of between the hook stick and the handle. Referring more particularly to Fig. 6, there is shown a handle 70 mounted on an operating shaft 71 so that said handle is capable of pivoting relative to the shaft 71 but is suitably restrained from axial movement with respect. to the shaft.

The handle 70 is provided with an apertured portion 70a of ring-shape which is adapted to receive a hook stick 85 for effecting pivotal movement of the handle about the axis of shaft 71. This pivotal movement of the handle, in a counterclockwise direction,v is normally transmitted to the shaft 71 by a releasable linkage 73 which comprises a crank arm 74 keyed to the shaft 71 and a latch member 75 suitably pivoted by a pin 76 on the handle 79. The latch member is formed with a shoulder 77' which normally engages behind a projection 78 carried by the crank arm 74. For biasing the latch member and the projection into latched relationship there is provided a torsion spring surrounding the pin 76 and tending to rotate the latch member counterclockwise about pin 76.

Operation of the mechanism of Figs. 6 and 7 is as follows. When it is desired to manually close the circuit breaker by moving the handle from the position of Fig. 6 to the position of Fig. 7, the hook stick 85 is first inserted into the apertured portion of the handle. The hook stick is then lifted to eifect counterclockwise pivotal movement of the handle about the shaft 71.. This pivotal movement of the handle is transmitted to the shaft 71 by the releasable linkage 73 until a screw 80, adjustably fixed to the frame structure 81, engages the surface 82 of the latch member 75, thereby causing the latch. member to pivot clockwise about pivot 76 so as to disengage the shoulder 77 from the projection 78. As soon as this disengagement occurs, the operating shaft 71 is uncoupled from force-transmitting relationship with the handle 70 and the hook stick 85, the'instant of the uncoupling being illustrated in Fig. 7. Thus, if the operating shaft 71 is called upon to move to open position immediately after being moved to closed position, it is free to do so even though an operator might inadvertently hold the hook stick in the elevated or closed position of the circuit breaker handle 70.

To manually open the circuit breaker when the handle 70 is in the closed position of Fig. 7, it is necessary merely to rotate the handle 70 in clockwise direction by means of the hook stick engaged in apertured portion 70a. This particularly, the elongated portion 75a constitutes a stop which is effective to insure that the latch 75 will always be maintained on the left-hand side of the projection 78, as seen in the drawings.

While I have shown and described particular embodiments of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made Without departing from my invention in its broader aspects and I, therefore, intend in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An operating mechanism for a circuit breaker comprising frame structure, an operating shaft pivotally mounted on said frame structure, a manually operable handle member mounted on said operating shaft and having a generally ring-shaped portion which receives a hook stick, coupling means associated with said handle and normally interrelating the hook stick and the operating shaft in force-transmitting relationship, and release arms disposed on said frame structure and cooperating 6 with said coupling means to automatically uncouple said hook stick from force-transmitting relationship with said shaft after predetermined pivotal movement of said shaft.

2. An operating mechanism for a circuit breaker comprising rame structure, an operating shaft pivotally mounted on said frame structure, a manually operable handle member mounted on said operating shaft and having a portion which receives a hook stick, coupling means associated with said handle and normally interrelating the hook stick and the operating shaft in forcetransmitting relationship, and adjustable release means associated with said frame structure and cooperating with said coupling means to automatically uncouple said hook stick from force-transmitting relationship with said shaft after predetermined pivotal movement of said shaft.

3. An operating mechanism for a circuit breaker comprising frame structure, an operating shaft pivotally mounted 'on said frame structure, a handle member mounted on said shaft and having a portion which receives a hook stick for effecting movement of said shaft, releasable coupling means normally interrelating the hook stick and the shaft in force-transmitting relationship, said releasable coupling means comprising a latch member, and release means associated with said frame structure, said release means being positioned to engage said latch member so as to automatically uncouple the hook stick from force-transmitting relationship with said operating shaft after a predetermined movement of said handle.

4. An operating mechanism for a circuit breaker comprising frame structure, a manually-operable handle member pivotally mounted on said frame structure and having a generally ring-shaped apertured portion which is adapted to receive a hook stick for effecting operation of said handle, retaining structure carried by said handle member and effective to releasably retain said hook stick in said aperture in force-transmitting relationship with said handle member, release means associated with said frame structure for rendering said retaining structure ineffective to retain said hook stick in said aperture after predetermined pivotal movement of said handle.

5. An operating mechanism for a circuit breaker comprising frame structure, a manually-operable handle member pivotally mounted on said frame structure and having an apertured portion which is adapted to receive a hook stick for effecting operation of said handle, retaining structure carried by said handle member and effective to releasably retain said hook stick in said aperture in force-transmitting relationship with said handle member, and adjustable release means associated with said frame structure for rendering said retaining structure ineffective to retain said hook stick in said aperture after predetermined pivotal movement of said handle.

6. An operating mechanism for a circuit breaker comprising frame structure, a manually operable handle member pivotally mounted on frame casing structure and having an apertured portion which is adapted to receive a hook stick for eifecting operation of said handle, retaining structure cooperating with said handle member and effective to releasably retain said hook stick in said aperture in force-transmitting relationship with said handle member, said retaining structure comprising a lever member extending at least partially across said apertured portion and releasable latch means adapted to hold said lever member in force-transmitting relationship with said handle member, and release means associated with said frame structure for rendering said retaining structure inefiective to retain said hook stick in said aperture after predetermined pivotal movement of said handle.

7. An operating mechanism for a circuit breaker comprising frame structure, a manually operable handle member pivotally mounted on said frame structure and having an apertured portion which is adapted to receive a hook stick for efifecting operation of said handle, a lever member extending at least partially across said apertured portion and releasable latch means normally latching said lever member in force-transmitting relationship with said handle member, and release means associated with said frame structure and comprising an element engageable with said latch means to effect unlatching of said lever member after predetermined pivotal movement of said handle.

8. An operating mechanism for a circuit breaker comprising frame structure, a manually operable handle member pivotally mounted on said frame structure and having an open-sided apertured portion which is adapted to receive a hook stick for effecting operation of said handle, retaining structure carried by said handle member and effective to releasably retain said hook stick in said aperture in force-transmitting relationship with said handle member, said retaining structure comprising a lever member extending at least partially across the open side of said apertured portion and releasable latch means adapted to maintain said lever member in force-transmitting relationship with said handle member, and release means associated with said frame structure for rendering said retaining structure ineffective to retain said hook stick in said aperture after predetermined pivotal movement of said handle, said release means comprising projecting structure positioned to engage said latch means.

9. An operating mechanism for a circuit breaker comprising frame structure, a manually operable handle member pivotally mounted on said frame structure and having an open-sided apertured portion which is adapted to receive a hook stick for effecting operation of said handle, a lever member extending at least partially across the open side of said apertured portion and releasable latch means normally latching said lever member in forcetransrnitting relationship with said handle member, and release means associated with said frame structure and comprising projecting structure engageable with said latch means to effect unlatching of said lever member, said projecting structure comprising a threaded member adjustably mounted on said frame structure.

10. An operating mechanism for a circuit breaker comprising frame structure, a manually-operable handle member pivotally mounted on said frame structure and having an apertured portion which is adapted to receive a hook stick for efiecting operation of said handle, retaining structure carried by said handle member and effective to releasably retain said hook stick in said aperture in force-transmitting relationship with said handle member, adjustable release means associated with said frame structure for rendering said retaining structure ineffective to retain said hook stick in said aperture after predetermined pivotal movement of said handle, said adjustable release means comprising a cam plate adjustably mounted on said frame structure and engageable with said hook stick to earn said hook stick away from said handle member after said predetermined movement of said handle member.

11. An operating mechanism for a circuit breaker comprising frame structure, a manually-operable handle member pivotally mounted on said frame structure and having an apertured portion which is adapted to receive a hook stick for effecting operation of said handle, retaining structure carried by said handle member and effective to releasably retain said hook stick in said aperture in force-transmitting relationship with said handle member, adjustable release means associated with said frame structure for rendering said retaining structure ineffective to retain said hook stick in said aperture after predetermined pivotal movement of said handle, said adjustable release means comprising a cam plate pivotally mounted on said frame structure and adjustably positioned by a threaded member, said cam plate being engageable with said hook stick to cam said hook'stick 8 away from said handle member after said predetermined pivotal movement.

12. An operating mechanism for a circuit breaker comprising an operating shaft, a handle member mounted on said shaft and having a portion which receives a hook stick for effecting movement of said shaft, releasable coupling means between said shaft and said handle for normally interrelating the handle and the shaft in force-transmitting relationship, said releasable coupling means comprising crank structure connected to rotate with said shaft and releasable latch means normally latching together said handle and said crank structure, release means cooperable with said latch means to uncouple said handle, and said shaft from force-transmitting relationship after predetermined pivotal movement of said shaft. 7

13. An operating mechanism for a circuit breaker comprising an operating shaft, a handle member mounted on said shaft and having a portion which receives a hook stick for effecting movement of said shaft, releasable coupling means between said shaft and said handle for normally interrelating the handle and the shaft in force-transmitting relationship, said releasable coupling means comprising crank structure connected to rotate with said shaft and releasable latch means normally latching together said handle and said crank structure, release means cooperable with said latch means to uncouple said handle and said shaft from force-transmitting relationship after predetermined pivotal movement of said shaft, said release structure comprising a projection which engages said latch means after said predetermined pivotal movement.

14. In a circuit recloser of the type comprising frame structure, an operating shaft pivotally mounted on said frame structure, a handle mounted on said operating shaft and movable from a first into a second position in response to lock-out of said recloser and manually returnable toward said first position to effect reclosing of said recloser, said handle having a generally ringshaped portion which receives a hook stick for operating said handle between said first and said second positions; the combination with said handle of coupling means operatively interconnecting the hook stick and the operating shaft in force-transmitting relationship, and release means disposed on said frame structure and cooperating with said coupling means to automatically uncouple said hook stick from force-transmitting relationship with said shaft after predetermined movement of said handle from said second toward said first position.

15. In a circuit recloser of the type comprising frame structure, an operating shaft pivotally mounted thereon, a handle mounted on said operating shaft and movable from a first into a second position in response to lockout of said recloser and manually returnable toward said first position to effect reclosing of said recloser, said handle having a portion which receives a hook stick for'operating said handle between said first and second positions; the combination with said handle of latch means effective when latched to operatively connect said hook stick and said operating shaft in force-transmitting relationship, said latch means being operable when unlatched to uncouple said hook stick from forcetransmitting relationship with said shaft, and release means engageable with said latch means after predetermined movement of said handle toward said first position to unlatch said latch means.

Kyle et al July 26, 1949 Harper Nov. 14, 1950

Images