US2843699A - Safety lock-out attachment for automatic reclosing circuit breakers - Google Patents

Description

July 15, 1958 D. L. LEATHERBERRY 2,843,699

SAFETY LOCK-OUT ATTACHMENT FOR AUTOMATIC RECLOSING CIRCUIT BREAKERS Filed May 8, 1956 5 Sheets-Sheet 1 IN V EN TOR. DONALD L. LEATHERBER RY MW M 19% ATTORNEYS July 15, 1958 D. L. LEATHERBERRY SAFETY LOCK-OUT ATTACHMENT FOR AUTOMATIC RECLOSING CIRCUIT BREAKERS Filed May 8, 1956 5 Sheets-Sheet 2 INVENTOR.

- DONALD L. LEATHEJZgRRY ATTORNEYS d July 15,1958 D. L. LEATHERBERRY 2,843,699

SAFETY LOCKOUT ATTACHMENT FOR AUTOMATIC RECLOSING CIRCUIT BREAKERS Filed May 8, 1956 5 Sheets-Sheet 5 INVENTOR. DONALD L. LEATHERBERRY ATTORNEYS y 1958 D. L. LEATHERBERRY 2,84

SAFETY LOCK-OUT ATTACHMENT FOR AUTOMATIC RECLOSING CIRCUIT BREAKERS Filed May 8, 1956 5 Sheets-Sheet 4 IN V EN TOR.

.1 .2 E 4 DONALD L. LEATHER ERRY ATTORNEYS y 1958 D. L. LEATHERBERRY 2,843,699

SAFETY LOCK-OUT ATTACHMENT FOR AUTOMATIC I RECLOSING CIRCUIT BREAKERS Filed May 8, 1956 5 Sheets-Sheet 5 I INVENTOK DONALD L. LEATHERB RRY BY M E15. 5 W #W ATTORNEY 5 2,843,599 Patented July 15, 1958 SAFETY LOCK- PUT ATTACHMENT FOR AUTO- MATIC RECLOSING CIRCUIT BREAKERS Donald L. Leatherberry, Greensburg, Pa., assignor to ll-TJE Circuit Breaker Company, Philadelphia, Pa a corporation of Pennsylvania Application May 8, 1956,,Serial No. 583,536

8 Claims. (Cl. 200-89) This invention relates to an improvement on the structure shown in U. S. Patent No. 2,693,514 to Smith and 2,738,394 to Matthews and is more specifically directed to a safety lock-out attachment for automatic reclcsers which will maintain the recloser contacts open after their first operation to the open position.

Reclosers are normally installed to give protective action to the circuits on which they are located. The automatic recloser provides this protective action by a series of opening and closing operations until the fault current source is isolated from the circuit. After a pre determined number of interrupting and closing operations, the reclosers will lock in a predetermined position if the trouble cannot be isolated.

Frequently high voltage lines are serviced by operating crews with the circuit operating under normal conditions; that is, the lines are worked hot and due ,recaution must be taken by the operating personnel due to the danger caused by their proximity to these high voltage conductors.

As a safety feature, it is desirable that the reclosers be easily adjusted so that they will not perform their complete cycle of operations in case of a fault. For example, a lineman may wish to do some repair work on the line without interrupting the circuit and be able to easily adjust the recloser so that it will only open once and stay in the open position in case of a fault.

This safety adjustment would be of great value to the lineman because in case of some accident on the energized circuit, he would be reassured that once the circuit was interrupted by the recloser, it would not close back in and re-energize the circuit. For example, the lineman might accidentally drop .a wrench or other tool on an energized circuit below him, causing a fiashover. With the first interruption of the recloser, occurring very quickly, the lineman might escape injury and could then extricate himself as soon as the circuit became deenergized. However, if the recloser were allowed to continue its complete cycle of operations, he would be exposed to several additional arcs of long: duration with great hazard to himself.

Nore specifically, I provide for the. recloser a manual operating means which carries a first latch and a manually operable safety lock-out means which carries a second latch. The manual operating means is so constructed as to move the recloser contacts to a disengaged position and to latch them in thisdisengaged position by means of the first latch associated with the manual operating means.

The manually operable safety lock-out means is then provided so as to be completely independent of the manual operating means and carries a second latch. When this manually operable safety lock-out means is moved to a safety lock-out position, it' positions the second latch associated therewith so as to latch the recloser contacts in a disengaged position: when these contacts are automatically movedlto this disengaged or open position, which thereby defeats the automatic sequential operation that would follow in the absence of this safety lock-out means.

Accordingly, a primary object of my invention is to provide a safety lock-out attachment for reclosing devices which is positionable independently of the manual operating means to maintain the recloser contacts disengaged upon the first automatic operation of the recloser contacts to this open or disengaged position.

Another object of my invention is to provide a safety lock-out device for reclosers which has .a relatively small number of parts and provides reliable operation.

Still another object of my invention is to provide a safety lock-out device for reclosers which gives a visual indication of its position.

A further object of my invention is to provide a recloser with a manual operating means having a first latch for manually opening and latching the reclosing contacts and a safety lock-out means which is manually operable to position a second latch which will maintain the re closer contacts open upon their first movement to their open position.

A still further object of my invention is to provide a safety lock-out device which may be easily attached to reclosing devices in the field.

These and other objects of my invention will become apparent from the following description when taken in conjunction with the drawings in which:

Figure 1 shows a schematic diagram of the type of recloser towhich my novel invention may be applied.

Figure 2 shows an exploded perspective view of the type of recloser mechanism to which my novel safety lock-out attachment may be applied.

Figure 3 shows a top cross-sectional view of a recloser adapted with the type mechanism seen in Figure 2.

Figure 4 shows a view of Figure 3 taken across the line 4-4.

Figure 5 shows my novel safety lock-out attachment as applied to the type mechanism seen in Figure 2.

Figure 6 shows a fractional side cross-sectional view of the safety lock-out attachment of Figure 5.

Figure 7 shows a view of Figure 6 taken along the line 77.

Figure 8 shows a side cross-sectional view similar to Figure 3 which includes my novel safety lock-out attach ment as seen in Figure 6.

Referring now to Figure l which shows a typical recloser, it is seen that terminal 10 is connected to a magnet winding 11 and winding 11 is connected in parallel with magnet windinglZ and contact assembly 13, this parallel combination then being connected in series with a movable contact 14 which is movable to an open and closed position with respect to a cooperating contact 15. During normal operation, current proceeds from terminal it) through the magnet winding 11, contact 13 (which is closed under normal conditions), movable contact 14 and terminal 16.

Upon the occurrence of an overload, magnet winding 11 will be energized beyond a predetermined value and in some desired manner, this overenergization will cause contact disengagement of the contacts i3 so as to force current flow through the winding 12. l linding 12, however, is so constructed as to cause the movable contact 14 to move to a disengaged position with respect to contact 15 upon energization thereof so as to etfect disengagement of the contacts.

After the are between separated contacts 14 and 15 is interrupted, winding 11 is dc-energized and contacts 13 immediately close. A timing. mechanism, which is here merely illustrated as the box 17 and may be seen in more detail in conjunction with the above noted U. S,

3 Patents 2,693,5l4 and 2,738,394, will allow a re-engagement between the recloser contacts.

In the event that the fault condition is still on the line, magnet winding 11 will again be energized beyond its predetermined value so as to cause control contact 13 to reopen to thereby cause re-energization of coil 12 and a reopening of the contact 14.

This sequence is then continued for a predetermined number of times under a continuing fault condition until the timing mechanism 17 will lock the control contact 13 and the contacts 14 and 15 in a predetermined position.

It is desirable that contact 14 be movable to a disengaged position by a manual means as is well known in the art, and it is further desirable that the cyclic opera tion of contacts 14 and 15 to their open and closed positions responsive to fault conditions be defeatable by a safety lock-out device so that an operator working on an energized line may be sure that the reclosing contacts will be maintained in the open position upon their first movement thereto.

Figures 2, 3 and 4 show a recloser mechanism for allowing manual operation of recloser contacts. As may be seen in Figures 3 and 4, the recloser is comprised of a head casting, a portion of which is seen at 18. The manual operating mechanism which is attached to the casting 18 of Figures 3 and 4 is now seen in Figures 2, 3 and 4 as comprising the manual operating lever 19 which is pivoted on a shaft 20 which also supports internal lever 21 and external lever 22.

The shaft 20 is then supported at the housing portion 23 in any desired manner. The lever 21 is then seen as being pivotally connected at the pivot point 23 to an operating arm 24 which is connected to the movable contact 14 of Figure 1 so as to move this contact into and out of engagement with respect to its cooperating Contact independently of the automatic operating means.

A first latch 25 is pivotally supported by the shaft 2'7 which is mounted at portion 26 of the casting support in any desired manner and a spring biasing means 28 is provided for the latch 25 so as to bias this latch in a clockwise direction with respect to Figures 2 and 4.

As may best be seen in Figures 2 and 4, the latch 25 is provided with a detent 29 which is engageable with a pin 39 which is an integral part of the operating lever 19.

it is this engagement between the pin 30 and detent 29 which maintains latch member 25 in its inoperative position of Figures 2, 3 and 4 and similarly in view of the spring bias of spring 28, the operating handle 19 is maintained in the position most clearly shown in Figure 4.

It is to be further noted that the force exerted by detent 29 to hold the manual operating lever in its inactive position may be controlled in magnitude not only by the strength of the latch biasing spring 23 but by the contour of detent 29 as well.

As is seen most clearly in Figures 2 and 4, the detent- 2-9 is further constructed so that the portion bearing against pin 33 is extended upward. This construction prevents pin 30 from disengaging detent 29 when manual operating lever 19 is rotated counterclockwise until it bears against housing portion 31 which acts as a stop.

The external lever 22 carries as an integral portion thereof a pin 32 and an extension 33 as is best seen in Figures 2 and 3 where extension 33 is engageable with portion 34 of the lever arm 19 and pin 32 is engageable with surface 35 of latch 25.

It is now to be noted that since external lever 22 and internal lever 21 are rigidly connected to rotate on the common shaft 20 upon automatic operation of the recloser to the contact open and contact closed positions, this opening and closing motion will be transmitted through the link 24 to levers 21 and 22. Since, however, under this condition the manually operable lever 19 is in the inactive position, the pin extension 32 may rotate freely since it will not engage surface 35 of latch 25 during this rotation.

A counting mechanism 60, as seen in Figures 3 and 8, is connected to the extension 33 of external lever 22. it is seen that this counting mechanism 60 is mounted on a cover 36 which may be of transparent material so that the position of indicator 37 which is mounted on shaft 20 may be noted, which will give an indication of the open or closed position of the recloser contacts.

In order to open the recloser of Figures 2, 3 and 4- manually, the pull ring 38 of manual operating lever may be engaged by a hook stick and pulled clockwise with sufiicient force to overcome the blocking force exerted by detent 29 on the pin 30. The latch 25 is then rotated counterclockwise until the detent 29 and pin 35 are disengaged. At this point, as may be seen most clearly in Figure 2, the surface 34- of manual operating lever 19 engages the extension 33 of external lever 22 so that further clockwise motion of pull ring 38 acts to open the recloser.

During this manual opening, it is seen that the recloser will automatically be locked open since as pin 30 is moved away from detent 29, latch 25 will be rotated clockwise by its biasing spring 28 and surface 35 of latch 25 engages pin 32 of external lever 22. The contour of surface 35 is such that latch 25 will not move as the pin 32 traverses surface 35. After the pin 32 completely passes over surface 35 of latch 25 and travels beyond latch surface 35 to depression 39 in latch surface 35, latch 25 will rotate clockwise until pin 32 is trapped in the depression 39.

Thus, when the recloser contact attempts to move to its engaged position after being disengaged by external operating handle 19, the engagement between pin 32 and depression 39 will provide a latch to defeat this reclosing operation and the recloser contacts will be maintained disengaged.

In order to close the recloser following a manual lockout, pull ring 38 of manual operating lever 19 is engaged and rotated in a counterclockwise direction against the stop 31. In so doing, pin 30 of manual operating lever 19 will move into engagement against the surface of latch 25 so that further counterclockwise motion of pin 30 will cause a counterclockwise rotation of latch 25 about its pivot point 27 to thereby disengage pin 32 and depression 39 of latch 25.

Hence, the external operating lever 22 is disengaged from the first latch 25 and the recloser contacts may be moved to an engaged position through the connecting link 24.

Immediately prior to the operating lever 19 reaching its stop 31, the pin 30 will slide completely past the surface 40 of latch 25 so as to permit detent 29* to be rotated in a clockwise direction to engage pin 30.

It is important to note that if the counterclockwise force on pull ring 38 is removed after the depression 39 of latch 25 disengages pin 32 of external operating lever 22, the extension 33 of external operating lever 22 will engage surface 34 of operating lever 19 so as to rotate manual operating lever 19 until detent 29 engages pin 3%). This novel feature provides positive action for the manual closing mechanism and will prevent the recloser contacts from being fully closed without also latching external operating lever 22 in its inactive position shown in Fig ures 2, 3 and 4.

In accordance with my novel invention, a safety lockout attachment may now be added to the manual operating mechanism of Figures 2 and 3 and may be seen in conjunction with Figures 5, 6 and 7. It is to be noted that the exploded perspective view of Figure 5 is identical to that of Figure 2 with the exception of the safety lockout attachment.

Referring now to Figures 5, 6 and 7, it is seen that the safety lock-out attachment is comprised of a latch 41 which is identical in construction with latch 25 and its associated biasing spring 42 which is identical to the biasing spring 28 associated with latch 25. Both latch 41 and its biasing spring 42 are mounted on the same shaft 26 which contains the latch 2'3 and a safety lock-out lever 43 is pivotally mounted on a shaft 44 which is connected to housing portion 26 in any desired manner.

By way of example, the housing portion 26 of Figure 3 may have a mounting hole tapped therein to receive a bolt constructed to provide a shaft such as mounting shaft 44 for the safety lock-out lever 43. A detent 45 is then seen as being provided for the second latch member 41 while the safety lock-out lever 43 carries a pin 46 integral therewith. The engagement between pin 46 and detent 45 maintains both the safety lock-out lever 43 and latch 41 in their negative positions shown in Figures 5, 6 and 7 in view of the biasing force of spring 42.

In the case of safety lock-out lever 43, as was the case of manual operating lever 19, the force required to hold safety lock-out lever 43 in its negative position may be determined by the contour of detent 45,

Similarly, the portion of detent 45 which bears against pin 46 to hold latch 41 inactive is extended upward so as to prevent disengagement therebetween when safety lockout lever 43 is rotated counterclockwise until the latter bears against housing portion 4'? which acts as a stop.

The previously described pin 32 of external operating lever 22 of Figures 2, 3 and 4 is made long enough to engage both latches 25 and 41 as may be seen in Figure 8. During automatic operation of the recloser contacts, it is then seen that pin 32 may rotate freely throughout its angle of rotation so long as latches 25 and 41 are maintained in their negative positions.

In order to activate the safety lock-out feature of my novel invention, the safety locloout lever 43 is pulled clockwise with sufficient force to overcome the blocking force exerted by detent 45 on pin 46. Latch 41 then rotates counterclockwise until detent 45 disengages pin 46. Safety lock-out lever 43 then rotates freely until extension 48 bears against housing portion 43 as may be seen in Figure 7 so as to act as a stop.

Extension 48 also operates to give an indication that the safety lock-out is active. When extension 48 is rotated to the active position, it will for the first time be visible from outside the housing.

During the rotation of safety lock-out lever 43 in a clockwise direction, it is seen that as was the case of latch 25, the latch 41 will rotate clockwise until its surface 50 engages pin 32.

If now the recloser is automatically opened with the safety lock-out device active and pin 32 bearing against surface 50, then the pin 32 will travel across the surface 50 to the depression 51 as may be seen more specifically in Figures 5 and 7 so as to effect a latching engagement between the latch 41 and the external operating lever 22, thereby latching the recloser contacts in the open position.

Either to inactivate this safety lock-out feature of Figures 5, 6, 7 and 8 or to manually reclose the recloser after automatic operation, the safety lock-out lever 43 is rotated counterclockwise until it engages the housing stop 47. In so doing, pin 46 of safety lock-out lever 43 engages surface 53 of latch 41 and rotates this latch counterclockwise until pin 46 moves into engagement with the detent 45. If the recloser were latched open on safety lock-out, the latch depression Ell would have disengaged pin 32 of external lever 22, thereby permitting the recloser contacts to close while pin 32 traverses latch surface 5'0.

When the recloser is manually latched open and the safety lock-out lever 43 is moved to its active position, pin 32 will latch with depression 51 due to the contour of surface 51. Hence, if the recloser contacts are closed on a fault, the safety lock-out Will operate to latch the recloser open. This feature is very desirable when a circuit is being tested and it is possible that faults exist on the line.

If the counterclockwise force on the safety lock-out lever 53 is removed after disengagement between pin 32 and depression 51 of the second latch 41 and before latch detent 45 engages pin 46, safety lock-out lever 43 will rotate clockwise because of its own weight until lever extension 48 engages stop 4-9. This condition leaves the safety feature active, but in view of the visual indication afforded by extension 48 in the active position, an operator is aware of the active condition of the recloser safety lock-out. Hence, the operator can, if desired, repeat the inactivating operation so as to place the recloser on automatic operation.

Although I have here described preferred embodiments of my invention, many variations and modifications will now be evident to those skilled in the art, and I prefer, therefore, to be limited not by the specific disclosure herein but only by the appended claims.

I claim:

1. In a reclosing circuit breaker having a first and second cooperating contact, at least said first contact being normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means, a safety lockout operating means; a first and second latch means and a latch engaging means; said latch engaging means being operatively connected to said first contact, said manual operating means being operatively connected to manually operate said first contact; said manual operating means being operatively connectible to said first latch means for moving said first latch means to engage said latch engaging means and maintain said first contact in said open position; said safety lockout operating means being operatively connected to move said second latch to a position for latching said latch engaging means to maintain said first contact in said open position when said first contact is moved thereto.

2. In a reclosing circuit breaker having a first and second cooperating contact, at least said first contact being normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means having a first latch means associated therewith; said manual operating means being constructed to move said first contact to said open position and to move said first latch means to latch said first contact in said open position; a manually operable safety lockout means having a second latch; said manually operable safety lockout means being operatively connected to move said second latch to a safety lockout position; said second latch being operatively connected to latch said first contact in said open position when said first contact is moved thereto and said second latch is in said safety lockout position.

3. In a reclosing circuit breaker having a first and second cooperating contacts, at least said first contact being normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means, a safety lockout operating means; a first and second latch means and a latch engaging means; said latch engaging means being operatively connected to said first contact and movable therewith, said manual operating means being operatively connected to manually operate said first contact; said manual operating means being operatively connectible to said first latch means for moving said first latch means to engage said latch engaging means and maintain said first contact in said open position; said latch engaging means being free to move with said first contact when said manual operating means is in an inoperative position; said safety lockout operating means being operatively connected to move said second latch to a position for latching said latch engaging means to maintain said first contact in said open position When said first contact is moved thereto.

4. In a reclosing circuit breaker having a first and second cooperating contact, at least said first contact being normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means; a safety lockout operating means; a first and second latch means and a latch engaging means; each of said first and second latch means having an active and an inactive position with respect to said latch engaging means; each of said first and second latch means being operatively positioned to engage said latch engaging means when in said active position and said first contact is moved to said open position; said manual operating means being operatively positioned to allow movement of said first latch means to said active position and to thereafter be connected to said first contact for movement thereof to said open position; said manual operating means being constructed to allow movement of said second latch to said active position upon operation thereof.

5. In a reclosing circuit breaker having a first and second cooperating contact, at least said first contact being normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means, a safety lockout operating means; a first and second latch means and a latch engaging means; each of said first and second latch means having an active and an inactive position with respect to said latch engaging means; biasing means for each of said first and second latch means for biasing said first and second latch means to said active position; each of said first and second latch means being operatively positioned to engage said latch engaging means when in said active position and said first contact is moved to said open position; said manual operating means being operatively positioned to allow movement of said first latch means to said active position by said biasing means and to thereafter be connected to said first contact for movement thereof to said open position; said manual operating means being constructed to allow movement of said second latch to said active position upon operation thereof by said biasing means.

6. In a reclosing circuit breaker having first and second cooperating contacts, at least said first contact be ing normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means, a safety lock-out operating means; a first and second latch means and a latch engaging means; each of said first and second latch means having an active and an inactive position with respect to said latch engaging means; biasing means for each of said first and second latch means being operatively positioned to engage said latch engaging means when in said active position and said first contact is moved to said open position; said manual operating means being operatively positioned to allow movement of said first latch means to said active position by said biasing means and to thereafter be connected to said first contact for movement thereof to said open position; said manual operating means being operatively positioned to allow movement of said second latch to said active position upon operation thereof by said biasing means; said spring biasing means being operatively connected to bias said manual operating means and said safety lock-out means to an inoperative position.

7. In a reclosing circuit breaker having a first and a second cooperating contact, at least said first contact being normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means having a first latch means associated therewith; a manually operable safety loch-out means having a second latch means associated therewith; each of said first and second latch means having an active and an inactive position; biasing means for each of said first and second latch means for biasing said first and second latch means to said active position; each of said first and second latch means being operatively connected to maintain said first contact in said open position when in said active position and when said first contact is moved thereto; said manual operating means being op eratively positioned to allow movement of said first latch means to said active position and to thereafter be connected to said first contact for movement thereof to said open position; said manually operable safety lock-out means being operatively positioned to allow movement of said second latch to said active position upon operation thereof.

8. In a reclosing circuit breaker having a first and a second cooperating contact, at least said first contact being normally automatically operable to open and closed position a predetermined number of times in response to overloads; a manual operating means having a first latch means associated therewith; a manually operable safety lock-out means having a second latch means associated therewith; each of said first and second latch means having an active and an inactive position; biasing means for each of said first and second latch means for biasing said first and second latch means to said active position; each of said first and second latch means being operatively connected to maintain said first contact in said open position when in said active position and when said first contact is moved thereto; said manual operating means being operatively positioned to allow movement of said first latch means to said active position by said biasing means; and to thereafter be connected to said first contact for movement thereof to said open position; said operating means being operatively positioned to allow movement of said second latch to said active position upon operation thereof by said biasing means.

References Cited in the file of this patent UNITED STATES PATENTS 2,414,786 Links et al Jan. 21, 1947 2,483,602 Wallace et al Oct. 4, 1949 2,693,514 Smith Nov. 2, 1954 2,738,394 Matthews Mar. 13, 1956

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