US2348034A - Reclosing circuit-interrupting device - Google Patents

Description

y 2, 1944- R.H. S TOTENBUR REQLOSING CIRCUIT-INTERRUPTING DEVICE Filed April 16, 1942 y rm m 00 P tt 0 if m 5 7 .R v

Patented May 2, 1944 RECLOSING CIRCUIT-INTERBUPTING DEVICE Ralph H. Stotenbur, Pittsfield, Masa, assignor to General Electric Company, a corporation of New York Application April 16, 1942, Serial No. 439,164

8 Claims. (Cl. 200-126) My invention relates to a reclosing circuit-interrupting device and more particularly to a circuit-interrupting device comprising a plurality of fuses only one of which is connected in the associated circuit at a time. Specifically, my invention is an improvement on concurrently filed copending application of George F. Lincks, Serial No. 439,165, assigned to the same assignee as the present application.

Fuse cutouts of the reclosing type in which a second fuse link is connected into the circuit a predetermined time after the first fuse link has blown has been used quite extensively. In reclosing circuit-interrupting devices of the type in which fuse links are held under tension between arms biased for separation, one of these arms is often used as a current transfer switch to connect a second fuse link into the circuit after a predetermined time delay. For satisfactory operation, it is desired that this arm which serves as a current transfer switch initially moves at high speed to insure separation of the fuse link parts. Also, in order to insure completing the circuit through the second fuse link, this arm serving as a current transfer switch must move at high speed near the end of its path satisfactorily and efliciently to complete the circuit. For most satisfactory operation, it has also been discovered that a predetermined time should elapse after rupture of the fuse link before the circuit is closed through the second fuse link, and, consequently, in the prior-art arrangements, very complicated time-delay mechanisms have been required to accomplish the desired movement of the fuse link supporting arm which acts as a current transfer switch.

Accordingly, it is an object of my invention to provide a new and improved time-delay means for a reclosing circuit-interrupting device.

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 of this specification.

For a better understanding of my invention, reference may be had to the accompanying drawing in which Fig. 1 is a front elevational view of a reclosing circuit-interrupting device embodying my invention, Fig. 2 is a sectional view taken on line 2-2 of Fig. 1, Fig. 3 is a side view of the lower portion of the device illustrated in Fig. 1, and Fig. 4 is a development of a portion of the time-delay mechanism of my inven- Referring now to the drawing, I have illustrated an insulator or' insulating supporting member I0 which may be suitably supported from a pole or crossarm, not shown, as by a supporting strap or hanger, generally indicated at H, which is adapted substantially to surround a central portion I2 of reduced diameter of insulator H). A pair of spaced line terminals 13 and I4 are fixedly mounted on insulator ID in any suitable manner and are provided with means indicated at l5 and [6, respectively, for making connections with a transmission line or the like. Electrically connected to upper line terminal l3 and supported from insulator I0 is a conducting arm I! projecting outwardly from terminal I3. Conducting arm I! has been indicated as a relatively rigid member although it will be understood that a relatively resilient member might also be employed. Supported at the extreme outer end of conducting arm I! is a contact clip or jaw member 18 having rearwardly extending spring-biased jaw portions l9 which provide gripping means or fuse link receiving means for a fuse link to be described hereinafter.

Lower terminal 14 may be supported from insulator ill in any suitable manner as by cementing or the like or, as illustrated in the drawing by a strap 20 surrounding insulator l0 adjacent the lower end thereof. Line terminal 14 is provided with a forked extension 2| having openings 22 therein for accommodating a pivot pin 23 to which is connected a rigid conducting arm 24. The openings 22 in forked member 2| are slightly elongated in one direction, as indicated in Figs. 1 and 3, to permit a slight sidewise movement of rigid conducting arm 24 as will be described in greater detail hereinafter. Suitable spring means 25 are provided for biasing rigid conducting arm 24 so as to move downwardly away from conducting arm I! or in a clockwise direction as viewed in Fig. 3. Supported at the extreme outer end of lower conducting arm 24 is a contact clip of jaw member 26 substantially identical with jaw member l8 including fuse link receiving means for gripping a fuse link to be described hereinafter. It should be understood that, although conducting arms I! and 24 have been described as relatively rigid arms with suitable spring means for causing relative separation thereof, relatively resilient arms might be provided which are inherently biased for relative separation.

A first fuse link, generally indicated at 21, comprises a pair of flexible cables 28 spaced apart at their inner ends which are interconnected by a fusible element, not shown, enclosed within a tube 29 preferably formed of horn fiber or other material that is characterized by the ability to give off gas in the presence of the heat of an electric arc, which gas tends to extinguish said electric arc. At the outer ends of the cables 28 of fuse link 21 are provided fuse link terminals comprising loops 30 and stop members 3|. The loops 30 are provided so that the fuse link 21 may readily be handled by means of a switch stick and the stops 3| are provided so that the cable portions 28 will not slip through the gripping portions of the upper and lower jaws l3 and 28, respectively.

When the fuse link 21 is inserted in the gripping portions of Jaw members I8 and 26, it is held under tension as indicated in Fig. 1 by virtue of spring means 25. Fuse link 21 is hereinafter referred to as the first fuse link to distinguish it from a second fuse link used to reclose the circuit upon blowing of the first fuse link. It should be understood that the expression first fuse link" used in this specification and the claims referred to hereinafter refers to any fuse link inserted between conducting arms I1 and 24 whether it be the fuse link originally provided or a subsequently replaced fuse link, in other words, the expression is more indicative of the position of the fuse link rather than referring to any specific fuse link.

In order that a second fuse link may be connected into the circuit upon rupture of first fuse link 21, a second conducting arm 32 is connected to line terminal l3 which projects outwardly from insulator III at substantially right angles to conducting arm H to provide sufficient clearance between the fuse links which are supported by arms l1 and 32. The outer end of conducting arm 32 is provided with a contact clip or jaw member 33 substantially identical with jaw members l8 and 26 described heretofore. It should be understood that, although upper conducting arms l1 and 32 have been illustrated for supporting two separate fuse links, a single conducting arm, such as l1, might be provided for supporting both fuse links as is disclosed in the copending application of Sidney R. Smith, Jr., Serial No. 439,162, filed concurrently with this application and assigned to the same assignee as the present application.

Insulator I is also provided with a third terminal 34 which is adjacent to terminal H but spaced sufficiently therefrom for satisfactory insulating purposes under all voltage conditions normally encountered. Pivotally connected to third terminal 34 is a conducting arm 35 comprising a looped member having at the extreme outer end thereof a contact clip or jaw member 36 substantially identical with jaw members I8, 26, and 33, referred to above. As best shown in Fig. 2, the end of conducting arm 35 adjacent third terminal 34 which is the closed end of the loop is provided with portions 35 about which arm 35 pivots with respect to third terminal 34. A suitable spring 44 is connected to an extension 35" (see Fig. 2) of conducting arm 35, which biases arm 35 to rotate about portions 35' in a clockwise direction as viewed in Fig. 1. In the position of the arm 35 shown in Fig. 1, spring means 44 is under tension, thereby providing tension on a second fuse link, generally indicated at 31 insorted between the Jaw members 33 and 33 of conducting arms 32 and 35, respectively. second fuse link 31 is identical with first fuse link 21 and the corresponding parts thereof are designated by the same reference numerals as are the corresponding parts of fuse link 21.

Since the third terminal 34 associated with insulator I0 is normally insulated from line terminal l4, fuse link 31 is not connected between line terminals l3 and I4 when fuse link 21 is in the unblown condition. In order to connect second fuse link 31 into the circuit between line terminals l3 and I4 upon blowing of fuse link 21, rigid conducting arm 24 is adapted to rotate about pivot pin 23, rapidly separating the remaining portions of fuse link 21 and, consequently, rapidly extinguishing the are formed. At the extreme downward movement of conducting arm 24, it is adapted to be electrically connected with a switching member 33 electrically connected to third terminal 34 and supported thereby. At the extreme outer end of switching member 38, there are provided contact prongs or diverging portions 39 between which conducting arm 24 moves under the force of spring means 25 upon rupture of first fuse link 21 and the electrical circuit between arm 24 and switching member 33 is thereby completed. The electrical circuit from lower line terminal I4 to the lower terminal of fuse link 31 is thereby completed through conducting arm 24, switching member 38, third terminal 34, and conducting arm 35.

Since spring means 25 moves conducting arm 24 at high speed, it might be possible to reclose the circuit through second fuse link 31 before a temporary fault is cleared by first fuse link 21 and, accordingly, to prevent this undesirable operation, time-delay means are usually provided so that the circuit between line terminals I3 and I4 is reclosed only after a predetermined time has elapsed. As has been described in the above-mentioned copending application of Sidney R. Smith, Jr., it is desirable for satisfactory operation that conducting arm 24 upon blowing of the first fuse link 21 initially moves at high speed without any time-delay to insure highspeed separation of the terminals of first fuse link 21. Also, prior to electrical engagement between switching member 33 and conducting arm 24, it is desirable that arm 24 moves at fairly high speed to insure satisfactory completion of the circuit when these members finally engage with one another. Consequently, intermediate these two pe riods of high speed movement of am 24, it is necessary to interpose a time delay, or period of retardation. To obtain this rather complicated movement of arm 24, I provide a very simple time-delay mechanism which comprises a plate 40 suitably fastened or supported from line terminal l4 which has a portion 40' formed in the arc of a circle as indicated best in Fig. 3. An elongated opening 4| which may be punched out of the curved portion 40 of plate 40 is provided, which includes at either end thereof a substantially straight portion 42 and an intermediate serpentine portion 43. This elongated opening 4| is sufficiently wide to permit arm 24 which extends through this opening to move from the upper end of the elongated opening to the lower end of the opening under the force of spring means 25. Upon blowing of fuse link 21, arm 24 initially moves along the upper straight portion 42 of elongated opening 4| and, consequently, moves at high speed to produce a flipping action on the ends of first fuse link 21. As

soon as arm 24 enters the serpentine portion 43 of elongated opening 4|, 8. time delay effect is produced due to the sidewise pendulum motion of arm 24 required by this serpentine path and due to the friction as the arm 24 moves downwardly, it being understood that the time delay may be controlled by the length of this serpentine path. The sidewise pendulum motion of arm 24 is permitted by virtue of the slightly elongated openings 22 provided in forked member 2| as described above. When arm 24 leaves the serpentine portion 43 of elongated opening 4| and enters the final straight portion 42, it is again permitted to move at high speed under the force of spring means 24 to insure satisfactoryclosure of the circuit when arm 24 engages switching member 38. Th final position isindicated by dotted lines in 1'18. 3.

As a result of the improvements hereinbefore described, a reclosing circuit-interrupting device is provided in which a simple time-delay mechanism may be utilized and yet wherein high-speed separation of the fuse link parts upon rupture thereof is assured, the desired time delay between the rupture of the first fuse link and the insertion of the second fuse link into the circuit is obtained, and positive and eflicient completion of the circuit through the second fuse link is provided.

Although a preferred embodiment of the invention has been disclosed in complete detail so as to insure a complete understanding of the invention, it is contemplated that details of the disclosed structure are capable of modification and that other applications and features of the invention may occur to those skilled in the art. Hence, it is intended in the appended claims to cover all such modifications and changes as fall within the true spirit and scope of my'invention.

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

1. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically interconnecting said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link, current transfer means for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing of said first fuse link, and time-delay means including a plate having an elongated opening therein through which said current transfer means is adapted to move for causing said current transfer means to move first at high speed, then at low speed to give the desired time delay, and, subsequently, at high speed satisfactorily to complete the circuit through said second fuse link.

2. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically intercon necting said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link, current transfer means for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing of said first fuse link, and time-delay means including a plrte having an elongated opening therein through which said current transfer means is adapted to move, said elongated opening comprising a serpentine portion to retard the motion of said current transfer means to provide the desired time delay.

3. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically interconnecting said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link, current transfer mean for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing of said first fuse link, and time-delay means including a plate having an elongated opening therein through which said current transfer means is adapted to move, said elongated opening comprising a straight initial and final portion to permit high-speed movement of said current transfer means both initially and at the end of said current transfer operation and an intermediate serpentine portion to retard the movement of said current transfer means to produce the desired time delay between the blowing of said first fuse link and the reclosing of the circuit through said second fuse link.

4. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically interconnecting said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link, current transfer means for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing of said first fuse link, and time-delay means including a plate having an elongated opening therein through which said current transfer means is adapted to move, said elongated opening being so shaped as greatly to increase the path traveled by said current transfer means. thereby introducing the desired time delay between the blowing of said first fuse link and the reclosing of the circuit through said second fuse link.

5. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals fixedly mounted on said supporting member, a pair of conducting arms biased for relative separation projecting outwardly from said supporting member each terminating in a fuse link receiving means, each of said arms being electrically connected to one of said line terminals, a first fuse link carried between said fuse link receiving means, a third terminal adjacent to but spaced from one of said line terminals, a second fuse link electrically interconnecting said third terminal and the other of said line terminals, means including the projecting arm connected to said one line terminal adjacent said third terminal for connecting said second fuse link into the circuit between said line terminals upon blowing of said first fu e link, and time-delay means including a plate having an elongated opening therein through which said projecting arm connected to said one line terminal adjacent said third terminal is adapted to move, said elongated opening being so shaped as greatly to increase the path traveled by said projecting arm, thereby introducing the desired time delay between the blowing of said first fuse link and the reclosing of the circuit through said second fuse link.

6. In a reclosing circuit-interrupting device,

the combination of an insulating supporting member, a pair of spaced line terminals fixedly mounted on said supporting member, a pair of conducting arms biased for relative separation projecting outwardly from said supporting member each terminating in a fuse link receiving means, each of said arms being electrically connected to one of said line terminals, a first fuse link carried between said fuse link receiving means, a third terminal adjacent to but spaced from one of said line terminals, a second fuse link electrically interconnecting said third terminal and the other of said line terminals, means including the projecting arm connected to said one line terminal adjacent said third terminal for connecting said second fuse link into the circuit between said line terminals upon blowing of said first fuse link, and time-delay means including a plate having an elongated opening therein through which said projecting arm connected to said one line terminal adjacent said third terminal is adapted to move, said elongated opening comprising a straight initial and final portion to permit initial and final high-speed movement of said projecting arm and an intermediate serpentine portion to retard the movement of said projecting arm, thereby introducing the desired time delay between the blowing of said first fuse link and the reclosing of the circuit through said second fuse link.

7. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically interconnectlng said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link, current transfer means for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing oi said first fuse link, and means for causing said current transfer means to move along a serpentine path thereby greatly increasing the distance traveled by said current transfer means and,

consequently, introducing the desired time delay' between the blowing of said first fuse link and the reclosing of said circuit through said second fuse link.

8. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals fixedly mounted on said supporting member, a pair of conducting arms biased for relative separation projecting outwardly from said supporting member each terminating in a fuse link receiving means, each of said arms being electrically connected to one of said line terminals, a first fuse link carried between said fuse link receiving means, a third terminal adjacent to but spaced from one of said line terminals, a second fuse link electrically interconnecting said third terminal and the other of said line terminals, means including the projecting arm connected to said one line terminal adjacent said third terminal for connecting said second fuse link into the circuit between said line terminals upon blow ing of said first fuse link, and means for causing'said projectin arm connected to said one line terminal adjacent said third terminal to move along a serpentine path after rupture of said first fuse link, thereby greatly increasing the distance traveled by said projecting arm and, consequently, introducing the desired time delay between the rupture of said first fuse link and the reclosing of said circuit through said second fuse link.

RALPH H. STOTE'NBUR-

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