US2816985A

US2816985A - Circuit interrupting means

Info

Publication number: US2816985A
Application number: US409800A
Authority: US
Inventors: Sigurd I Lindell
Original assignee: S&C Electric Co
Current assignee: S&C Electric Co
Priority date: 1953-06-19
Filing date: 1954-02-12
Publication date: 1957-12-17
Anticipated expiration: 1974-12-17

Description

Dec. 17, 1957 3 S.I. LINDELL cmcurr INTERRUPTING mus 4 Sheets-Sheet 1 Original Filed June 19, 1955 IN V EN TOR.

Dec; 1-7; 1957 s. 1. UNDELL 2,816,985

I CIRCUIT INTERRUPTING MEANS Original Filed June 19, 1953 4 Sheets-Sheet 2 IN V EN TOR.

5 I z, y 5961727 110 e! 17, 1957 s. LINDELL CIRCUIT INTERRUPTING umns Original Filed June 19, 1953 4 Sheets-Sheet 3 VIII/ll) I till/(111 774 3 wfi w 9 1 I: W WW nillim.

I INVENTOR. 5574022 lmdeZl, BY

S. I. LINDELL CIRCUIT INTERRUPTING MEANS Dec. 17, 1957 4 Sheets-Sheet 4 Original Filed June 19, 1955 INVENTOR.

f garafluzded, W

United States Patent CIRCUIT INTERRUPTING MEANS Sigurd I. Lindell, Chicago, Ill., assignor to S & C Electric Company, Chicago, 111., a corporation of Delaware Original application June 19, 1953, Serial No. 362,891,

now Patent No. 2,671,142, dated March 2, 1954. Divided and this application February 12, 1954, Serial No. 409,800

7 Claims. (Cl. 200115.5)

This invention relates, generally, to electric circuit interrupters, and it has particular relation to the application circuit interrupters for disconnecting under a load a conventional circuit isolating or switching device, such as a disconnecting fuse, a disconnecting switch or the like, without drawing an are between the energized parts thereof which are separated or disconnected as an incident to the circuit isolating operation as usually attempted to be effected by a lineman by means of a switch stick and to necessary modifications of circuit isolating and interrupting devices to adapt them for use with such circuit interrupters. This application is a division of application Serial No. 362,891, filed June 19, 1953, now Patent No. 2,671,142, dated March 2, 1954.

It is sometimes necessary deenergize' a high voltage electric power circuit carrying load current by swinging a pivotally mounted fuse to open circuit position without rupturing its fusible elements. Or it may be necessary to accomplish this by opening the blade of a conventional disconnecting switch under these conditions, the switch blade having no particular means for interrupting the arc incident to its being opened. When these operations are performed, an arc is drawn between the energized parts last in engagement since, under the assumed conditions, load current or line current is flowing. The are is likely to cause severe burning of these parts or it may jump to .ground or to an adjacent circuit and create a fault causing damage. At any event it is likely that operation of one or more circuit interrupters closer to the power source will be required in order to clear the fault thus caused.

Accordingly, among the objects of this invention are: Toprovide for simply, eificiently and economically opening an energized current carrying high voltage electric power circuit by swinging a fuse or disconnecting switch blade to open position without rupturing the fusible element of the former and without causing the are between the energized parts of the fuse or the switch last to separate; to shunt the separable parts of the fuse or switch by an auxiliary circuit interrupter that is arranged to draw and, extinguish the are within itself after the parts of the fuse or disconnecting switch or other circuit breaking device have been separated; to extinguish the are quickly and positively within the auxiliary circuit interrupter without external arcing; and to provide for mounting the auxiliary circuit interrupter on an energized part of the fuse or switch so that it can be readily attached thereto and detached therefrom as manipulated by a live line stick.

Other objects of this invention will, in part, be obvious andin part appear hereinafter.

This invention is disclosed in the embodiment thereof and method shown in the accompanying drawings, and it comprises the features of construction, combination of elements, arrangement of parts and method of operation whichwillube exemplified in the construction and method hereinafter 'set forth" and the scope of the application of which will be indicated in the appended claims.

For a more complete understanding of the nature and scope of this invention, reference may be had to the following detailed description taken together with the accompanying drawings, in which:

Figure 1 is a view in side elevation of a conventional form of dropout fuse construction such as that described in more detail in Ramsey United States Patent No. 2,247,700, issued July 1, 1941, certain parts of the terminal assembly at the upper end being broken away in order to illustrate the details of construction;

Figure 2 is a top plan view of the circuit isolating device or dropout fuse shown in Figure 1;

Figure 3 is a view, in side elevation, of the dropout fuse construction shown in Figure 1, at a reduced scale, and illustrating the application of the auxiliary circuit interrupter of the present invention thereto for effecting the opening of the fuse or disconnecting device without causing arcing between the parts thereof last to separate;

Figures 4 and 5 are views, similar to Figure 3, showing successive stages in the opening of the fuse or disconnecting device by means of the auxiliary circuit interrupter;

Figure 6 is a view at an enlarged scale, certain parts being broken away, illustrating the general construction and arrangement of the auxiliary circuit interrupter, the view being taken looking from right to left with respect to the auxiliary circuit interrupter as illustrated in Figures 3, 4, and 5;

Figure 7 is a longitudinal sectional view of the auxiliary circuit interrupter, the separable contacts being shown in the fully closed position;

Figure 8 is a view, similar to Figure 7, but illustrating the relative location of the parts after the separable parts of the fuse have been separated and after the movable auxiliary interrupter contact has been operated only a slight distance from its cooperating relatively fixed contact;

Figure 9 is a view, similar to Figures 7 and 8, but illustrating the relative positions of the parts of the auxiliary circuit interrupter when its separable contacts are in the full open position; and

Figure 10 is a view, in side elevation, of a modified form of contact arm for gripping the pull ring of the fuse, disconnecting switch or the like.

Referring now particularly to Figure 1 of the drawings, it will be observed that the reference character 10 designates, generally, a circuit isolating device or switching device which, in this instance, is a dropout fuse construction such as described in more detail in Ramsey Patent No. 2,247,700, issued July 1, 1941, and referred to above. However, it will be understood that the present invention can be used in conjunction with other circuit isolating devices, such as disconnecting switches in which a switch blade is swung from the closed to the open position for the purpose of introducing an air gap into the circuit.

The particular dropout fuse construction 10 includes an insulator 11 which carries

terminal assemblies

12 and 13 at its ends for connection to line conductors as will be understood readily. Pivotally mounted at 14 on the lower terminal assembly 13 is a fuse tube that is indicated, I

generally, at 15. The fuse tube 15 contains a fusible element which is arranged to be ruptured on flow therethrough of excess current and mechanism is provided for automatically unlatching the fuse tube 15 from the upper terminal assembly 12 so that it can fall to the open circuit position. When this occurs, the circuit is interrupted within the fuse tube 15 and the arc incident thereto is extinguished. Ordinarily under fault conditions, the circuit will be interrupted within the fuse tube 15 before it swings out of contact with the upper line terminal assembly 12.

The present invention has to do particularly with the provision of mechanism for effecting the opening of the circuit under load by bodily moving the fuse tube to the open circuit position while it still contains a fuse link that has not been ruptured by overcurrent. Provision is made for accomplishing this while load current is flowing through the fuse tube 15 in such manner that no arc is drawn between it and the upper terminal assembly 12 during the circuit opening operation.

At its upper end the fuse tube 15 has a fuse tube terminal assembly indicated, generally, at This assembly includes a sleeve 17 that is slidable upwardly relative to the fuse tube 15 and formed integrally with the sleeve 17 is a hook is which is held in latching engagement with a roller 19 carried by the upper terminal assembly 12. When the fuse link within the fuse tube 15 is ruptured, the sleeve 17 is moved upwardly to such position that the hook 18 no longer engages the roller 19. This same operation can be accomplished by means of an operating arm 29 which is pivoted at on the fuse tube terminal assembly 16. At its outer end the operating arm 20 has a pull ring 22 which is arranged to be engaged by the prong of a switch stick or the contact arm of the auxiliary circuit interrupter to be described hereinafter. When the pull ring 22 is swung in a counterclockwise direction about the pivot 21, the sleeve 17 is moved upwardly so that the book 8 clears the roller 19. The fuse tube 15 then can be swung or allowed to fall to the open circuit position.

When the fuse tube 15 is operated in the manner just described by the prong of a switch stick engaging the pull ring 22, an arc will be drawn between the portions of the terminal assembly 12 and fuse tube terminal assembly 16 last to separate. As indicated above, such an arc may damage severely these terminal assemblies or it may cause a fault on the circuit. In accordance with the present invention, the fuse tube is can be unlatched from the upper terminal assembly 12 and swung to the open position without drawing an are between the

terminal assemblies

12 and 16. The manner in which this is accomplished, generally, is by providing a shunt circuit between the

terminal assemblies

12 and 16, unlatching the fuse tube terminal assembly in from the upper terminal assembly 12, swinging the fuse tube 1.5 to such a position that an air gap is provided between the

terminal assemblies

12 and 16 and then interrupting the circuit by separating contacts within the auxiliary circuit interrupter under such conditions that the arc is confined and extinguished quickly. The only modification required in the construction of the circuit breaker ill for accommodating the auxiliary circuit interrupter comprises providing the sleet hood 23, forming a part of the terminal assembly 12, with a transversely extending conducting arm 24. As will appear hereinafter, this provides a fixed support for the auxiliary circuit interrupter while it is being employed for swinging the fuse tube 15 to open position without arcing between the

terminal assemblies

12 and 16.

For the purpose of operating the dropout fuse it to the open position without arcing, a generally tubular auxiliary circuit interrupter, shown generally at 25, is provided. Its application to the dropout fuse in is illustrated in Figure 3 and the details of construction are shown more clearly in Figure 7 to which reference now will be had.

It will be noted that the auxiliary circuit interrupter 25 has a relatively fixed conducting member 26 at its upper end to which a metallic cap .27 is secured by cap screws 28. A conducting eye member 29 is pivoted or swivelcd at 39 on the metallic cap 27, and it comprises a pair of resilient contact extensions 31 which are bowed outward 1y as indicated at 32 for facilitating entry of the transversely extending conducting arm 2 5 carried by the sleet hood 23. In order to provide good contact engagement with the conducting arm 24, the upper portions 33 of the extensions 31 are positioned in side by side relationship and biased toward each other by the inherent resiliency of the contact extensions 31. Because of this construction, they grip the conducting arm 24 tightly therebetween. The upper ends 34 of the contact extensions 31 are turned outwardly, as shown, and interfit with a keeper 35 which not only limits the movement apart of the upper portions 33 but also serves as a stop to prevent relative movement betwecn the eye member 29 and the conducting arm 24 when a downward pull is applied to the ii to be described.

Depending from the relatively fixed conducting member 26 is an insulating sleeve 38. It may be formed of a suitable phenolic condensation product. Intermediate the ends of the insulating sleeve 38 is a ringlihe contact 39 that is electrically and mechanically connected by a conducting sleeve 4%) to the conducting member 26 at the upper end of the insulating sleeve 38. It will be observed that both the insulating sleeve 38 and the conducting sleeve at} are threaded into the underside of the conducting member 26. Cooperating with the ringlike contact 39 is a rodlilte contact 41 having a bifurcated resilient contact portion 4-2 at its upper end for engaging the ringlike contact 39. Below the ringlike contact 39 is a liner 43 of insulating material which is capable of evolving an arc extinguishing medium when subjected to the heat of the arc. The liner 43 may be formed of a stack of fibre rings or other suitable material for this purpose. With a view to restricting the area within which the arc can play between the

contacts

39 and 41 when they are separated, an insulating trailer 44 is connected to the rodlike contact 41 and is arranged to be moved conjointly therewith into the bore formed by the liner 4-3 of insulating material. The trailer 44 is also formed of a material which evolves an arc extinguishing medium. For example, it may be formed of methyl mythacrylate resin. Ports &5 are provided in the conduct ing member 26 and extend radially therefrom for venting the interior of the auxiliary circuit interrupter 25 so that destructive pressure will not be built up within it during the circuit interrupting operation. The rodlike Contact 41 is provided with a shoulder 46 spaced from its upper end for cooperating with a tubular stop member 47 that is carried by a metallic fitting 43 threaded in Figure 9 of the drawings, to limit the downward movement of the rodlike contact 41.

Provision is made for maintaining the rodlike contact 41 in engagement with the ringlike contact 39 as shown in Figure 7. For this purpose the rodlikc contact 41 is provided with a shoulder 52 near its lower end which is arranged to cooperate with resilient fingers 53 that are carried by and depend from the metallic fitting 48. A garter spring 54 surrounds the fingers 53 and urges their lower inturned ends into mechanical contact engagement with the underside of the shoulder 52. This construc tion serves to hold the rodlike contact 41 in the position where it is in engagement with the ringlilae contact 39. However, when sufficient force is applied to the rodlike contact 41, the shoulder 52 moves downwardly to such position that the resilient fingers 53 are moved out of engagement therewith, as shown in Figure 8, whereupon the rodlike contact 41 can move quickly toward the open circuit position.

It is important to know whether the

contacts

39 and 41 are in engagement or out of engagement. For this purpose an indicator 55 is employed. As shown in Figure 7, it constitutes an extension of the lower end of the rodlike contact 41. Its indicating function will be described in more detail hereinafter.

A flanged metallic fitting 56 is secured by a transverse pin 57 to the rodlike contact 41 at a position just below :ry circuit interrupter 25 in a manner the shoulder 52. This flanged metallic fitting 56 cooperates with a spacer sleevev58, depending from the metallic fitting 48, for limiting the upward movement of the rodlike contact 41 and positioning its upper end contact portion properly with respect to the ringlike contact 39.

Surrounding and telescoped with the insulating sleeve 38 and freely axially rotatable with respect thereto is a metallic sleeve 59. At its upper end the metallic sleeve 59 has an end ring 60 against the underside of which a coil compression spring 61 reacts. It will be observed that the coil compression spring 61 surrounds the insulating sleeve 38 and that its lower end bears against the flanged metallic fitting 56. The spring 61 is employed for effecting rapid movement of the rodlike contact 41 from the closed to the open position in a manner to be described.

With a view to maintaining contact engagement between the rodlike contact 41 and the metallic sleeve 59 as the. latter m'oves downwardly with respect to the insulating sleeve 38 while the former is held stationary by a the resilient fingers 53, resilient contact fingers 62 are secured to the underside of the flanged metallic fitting 56 and bear outwardly against the inner surface of the sleeve 59. At the lower end of the metallic sleeve 59 there is a closure disc 63 which is provided with apertures 64 for venting the interior of the auxiliary circuit interrupter 25. The closure disc 63 also has a central aperture 65 through which the indicator 55 projects and from which it may be withdrawn as shown in Figure 8.

It is desirable to limit the relative movement apart of the metallic sleeve 59 and the insulating sleeve 38 and to prevent accidental reclosure of the

contacts

39 and 41. For this purpose the latter is provided with an annular slot 66 and the former carries a detent 67 spring biased by a resilient arm 68 that is secured by a rivet 69 to the outer surface of the sleeve 59 near its upper end. The inner end of the detent 67 rides over the surface of the insulating sleeve 38 until it reaches the annular slot 66.

As shown in Figure 8, the detent 68 has moved through an opening 70 in the end ring 60 and into the annular slot 66 prior to the forcing of the shoulder 52 past the resilient fingers 53 and separation of the rodlike contact 41 from the ringlike contact 39 where it prevents any further downward movement of the metallic sleeve 59 with respect to the insulating sleeve 38. Should the downwardly acting force applied to the sleeve 59 be released, the detent 67 reposing in the annular slot 66, prevents the spring 61 from effecting accidental reclosure of the

contacts

39 and 41.

Intermediate the ends of the metallic sleeve 59 a metallic support bracket 73 is clamped. Formed integrally therewith, Figure 6, is an arm 74 which is arranged to receive a detachable fitting 75 mounted on the upper end of a live line stick 76. Ordinarily the live line stick 76 is a suitably seasoned and treated wood pole which has high insulating qualities and is arranged to be manipulated by a lineman on the ground for operating various live line tools which are employed for performing operations on a circuit while the conductors are energized at high voltage. The fitting 75 is clamped to the arm 74 by a bolt 77 and a cooperating wing nut 78.

Since the fuse tube 15 swings in an are about the pivot 14 and the pull ring 22 moves therewith, provision is made for accommodating this relative movement of the pull ring 22 with respect to the auxiliary circuit interrupter 25. In accordance with this invention, there is provided a contact arm, shown generally at 79, which is rockably mounted on the arm 74. For this purpose a shaft 80 is employed and it has formed integrally therewith a shoulder 81, Figure 7, which cooperates with a stop pin 82. The shoulder 81 and stop pin 82 limit the movement of the contact arm 79 in a clockwise direction but permit it to swing in a counterclockwise direction to the :position shown by the broken lines in Figure 7. A torsion spring 83, having one end 84 fastened to the arm 74 and the other end 85 fastenedto a flange 86 secured by a transversepin'87 to the outer end ofthe shaft 80,

serves to bias the contact arm 79 against the stop pin 82. If desired, the'shoulder 81 and stop pin 82 may be omitted and the spring 83can be arranged to function as a center-- ing spring biasing the contact arm 79 to the position shown by the full lines in Figure 7 and permitting it to swing therefrom in either direction as may be required in the manipulation of the auxiliary circuit interrupter 25.

Referring particularly to Figure 6, it will be observed that the contact arm 79 includes a shank 90 which is fixed on and carried by a head 91 which forms an integral part of the shaft 80. At its upper end the shank 90 has a contact finger 92 extending at right angles with a bulbous outer end 93 to facilitate entry intothe opening in the;

pull ring 22. With a view to maintaining electrical contact with the pull ring 22 a cooperating contact finger94 is employed. It extends parallel to the contact finger 92 and has an inclined outer end 95 to facilitate cooperation with the pull ring 22. The contact finger 94 extends at.

right angles from and is carried by a sleeve 96 which is telescoped over the shank 90 and which is biased up-. 1 wardly by a coil compression spring 97. Movement of the sleeve 96 with respect to the shank 90 is limited by a slot 98 in the sleeve 96 and a stop pin 99 extending therethrough from the shank 90.

It will be understood that the spring 83 transmits its force through the contact finger 92 to bear against the;

inside of the pull ring 22. Where this contact engagement is suflicient, particularly where the spring 83 func-. tions as a centering spring as described above, suflicient 7 contact pressure is maintained against the pull ring 22- so that, if desired, the cooperating contact finger 94 and- In such case parts associated therewith can be omitted. reliance is-placed on the biasing action of the spring 83 for maintaining the desired contact engagement.

In Figure 10 of the drawings, there is illustrated a modified contact arm construction. As shown generally at 102, the contact arm is constructed so that the contact fingers thereof bear radially outwardly against the opening of the pull ring 22. For this purpose there is provided a sleeve 103 which is carried by the head 91 on the outer end of the shaft 80. Projecting at right angles from the sleeve 103 is a contact finger 104 whose outer end 105 is inclined upwardly to facilitate entry into the pull ring 22. Slida-bly mounted within the sleeve 103 is a shank 106 having a transverse pin 107 extending therefrom through a slot 108 in the sleeve 103 to limit;

relative movement between the shank 106 and the sleeve 103. The shank 106 carries a contact finger 109 at itsupper end which extends parallel to the contact finger 104 and has an inclined outer end 110 to facilitate entry into the opening of the pull ring 22. The contact finger 109 also has a shoulder 111 which cooperates with the pull ring 22 to maintain mechanical and electrical engagement therewith. A coil compression spring 112.

reacts between the upper end of the sleeve 103 and a washer 113 secured to the upper end of the shank 10.6.

for biasing the contact finger 109 upwardly so as to maintain good mechanical and electrical contact engagement with the inner surface of the pull ring 22 at diametrically opposite locations.

In operation the auxiliary circuit interrupter, carried cuit interrupter, more particularly the longitudinal axis.

It will be understood that.

of the insulating sleeve 38. either form of

contact arm

79 or 102 can be employed. When the auxiliary circuit interrupter 25 is positioned as described, the

contacts

39 and 41 therein are in engagement and the parts are positioned as shown more clearly in Figure 7. A shunt circuit then is established between the upper terminal assembly 12 of the circuit breaker 10 and the fuse tube terminal assembly 16 through the conducting arm 24, eye member 29, relatively fixed conducting member 26, conducting sleeve 40,

contacts

39 and 41, flanged metallic fitting 56, resilient contact fingers 62, metallic sleeve 59, support bracket 73, and contact arm 79 to the pull ring 22.

Now the live line stick 76 is manipulated by pulling on it lengthwise to the position shown in Figure 4. Since the support bracket 73 is fastened to the metallic sleeve 59 and since the eye member 29 prevents movement of the insulating sleeve 38, the metallic sleeve 59 is moved away from the insulating sleeve 38, as shown in Figure 4, and compression of the coil spring 62 is begun. However, the resilient fingers 53 are strong enough to hold the rodlike contact 41 against the force initially exerted by the spring 61 and thus, while the metallic sleeve 59 is being moved downwardly to the position shown in Figure 4, the

contacts

39 and 41 remain in engagement completing the shunt circuit previously described. Since the contact arm 79, which is in engagement with the pull ring 22, moves downwardly with the metallic sleeve 59, as manipulated by the live line stick 76, the arm 20 isoperated so as to lift the sleeve 17 and remove the hook 18 from engagement with the roller 19. This is followed by a swinging movement of the fuse tube 15 to the position shown in Figure 4. Because the shunt circuit is maintained by engagement of the

contacts

39 and 41 within the auxiliary circuit interrupter 25, no arcing occurs between the

terminal assemblies

12 and 16 when they separate.

As illustrated in Figure 5, the continued manipulation of the live line stick 76 causes the fuse tube 15 to swing further away from the closed position. This is accompanied by a further compression of the spring 61. The metallic tube 59 is operated to the position shown in Figure 8 where the detent 67 enters the groove 66 and prevents further movement apart or reverse movement. After this occurs and the spring 61 has been compressed to a point where the force exerted by it is greater than the restraining force exerted by the resilient fingers 53 on the shoulder 52, they are no longer capable of restraining downward movement of the rodlike contact 41. Alternatively the coil compression spring may be compressed to the solid position Where the downward pull on the live line stick 76 is transmitted directly to the flanged metallic fitting 56. in either event, after the metallic sleeve 59 has been locked by the detent 67 against reverse movement, the rodlike contact 41 is moved downwardly to the position shown in Figure 8 of the drawings where its upper end is out of engagement with the ringlike contact 39. An arc is drawn therebetween and it plays on the bore of the liner 43 of arc extinguishing material. The spring 61 now biases the rodlike contact 41 downwardly through the metallic sleeve 59 to increase the distance between the upper end of the former and the ringlike contact 39. This effects a corresponding extension of the arc. The trailer 44 following the movement of the rodlike contact 41 into the bore in the liner 43 assists in extinguishing the arc in a manner readily understood. At this time the external isolating air gap between the

terminal assemblies

12 and 16 and the break distance over the insulating sleeve 38 are equal to or greater than the break distance between the

contacts

39 and 41 within the auxiliary circuit interrupter 25, thereby avoiding the likelihood of external rlashover due to high recovery voltage incident to the circuit interruption. While the rodlike contact 41 is moving downwardly through the metallic sleeve 59, contact engagement therebetween is maintained through the resilient contact fingers 62.

alt)

It will be observed that the indicator 55, as shown in Figure 8 of the drawings, is totally enclosed by the metallic sleeve 59 at the time that the contacts 39 and 4-1 are first separated. Further it will be observed that the indicator 55 projects from the bottom of the metallic sleeve 59 when the

contacts

39 and 41 are in engagement as shown in Figure 7. Also it will be noted that, when the

contacts

39 and 41 are in the fully opened position, the indicator 55 again projects from the lower end of the metallic sleeve 59. This provides a positive indication to the lineman of the position of the

contacts

39 and 41, so that he has definite knowledge that they are either in the fully closed or fully open position.

The lineman now manipulates the auxiliary circuit interrupter 25 in such manner as to disengage the eye member 29 from the conducting member 26. This is facilitated by the fact that the metallic sleeve 59 is rotatable about the longitudinal axis of the device. Thereafter he further manipulates the auxiliary circuit interrupter 25 to disengage the contact arm 79 from the pull ring 22. This allows the fuse tube 15 to swing to the full open position under the influence of gravity.

For further use, the auxiliary circuit interrupter 25 is restored to the closed position, shown in Figure 7, by withdrawing the detent 67 from the slot 66 and allowing the metallic sleeve 5? to be moved by the spring 61 back over the insulating sleeve 38, thereby operating the rodlike contact 41 back into contact engagement with the ringlike contact 39. Of course, this is accomplished only when the device is removed entirely from proximity to an energized part of the electric power system.

Since certain further changes can be made in the foregoing construction and different embodiments of the invention can be made without departing from the spirit and scope thereof, it is intended that all matter shown in the accompanying drawings and described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

What is claimed as new is:

1. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having separable energized conducting parts normally carrying line current and shunted by a separable contact type of auxiliary circuit interrupter having external conducting members to permit separation of said parts Without arcing therebetween and subsequent opening of the circuit by separation of the contacts of said auxiliary circuit interrupter, one of said separable conducting parts being relatively stationary and the other being carried at one end of a rigid elongated member, means pivotally mounting the other end of said elongated member, stationary conducting means rigidly secured to said one conducting part and detachably receiving one of said external conducting members of said auxiliary circuit interrupter and capable of resisting an endwisc pull thereon for operating said auxiliary circuit interrupter and for receiving the same from various angles in planes at right angles to each other, and conducting means on said other conducting part detachably receiving another of said external conducting members.

2. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having separable energized stationary and relatively movable conducting parts normally carrying line current, and an auxiliary circuit interrupter having separable contacts therein connected respectively to external conducting members cngaging said conducting parts, said conducting members being readily connectable to and disconnectable from sai conducting parts with one conducting member being sccured to the stationary conducting part and the other conducting member being movable with said movable conducting part.

3. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like,

having separable energized conducting parts normally carrying line current and shunted by a separable contact type of auxiliary circuit interrupter having a pair of external conducting members to permit separation of said parts without arcing therebetween and subsequent opening of the circuit by separation of the contacts of said auxiliary circuit interrupter, one of said separable conducting parts being relatively stationary and the other being carried at one end of a rigid elongated member, means pivotally mounting the other end of said elongated member, a laterally extending conducting arm rigidly secured to said one conducting part and detachably receiving one of said external conducting members of said auxiliary circuit interrupter and capable of resisting an endwise pull thereon for operating said auxiliary circuit interrupter and for receiving the same from various angles in planes at right angles to each other, and a ring memher on said other conducting part detachably receiving the other of said external conducting members.

4. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having separable energized conducting parts normally carrying line current and shunted by a separable contact type of auxiliary circuit interrupter having a pair of external conducting members to permit separation of said parts without arcing therebetween and subsequent opening of the circuit by separation of the contacts of said auxiliary circuit interrupter, one of said separable conducting parts being relatively stationary and the other being carried at one end of a rigid elongated member, means pivotally mounting the other end of said elongated member, a conducting arm rigidly secured to said one conducting part and extending transversely of the plane of movement of said rigid elongated member, said conducting arm detachably receiving said auxiliary circuit interrupter and being capable of resisting an endwise pull thereon for operating said auxiliary circuit interrupter and adapted to receive the same from various angles in planes at right angles to each other, and a ring member on said other conducting part detachably re ceiving the other of said external conducting members and movable therewith for moving said elongated member from closed position.

5. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having separable energized conducting parts normally carrying line current and shunted by an auxiliary circuit interrupter to permit separation of said parts without arcing therebetween, one of said parts being relatively stationary and the other being movable away therefrom, and a conducting member on each of said parts detachably receiving said auxiliary circuit interrupter.

6. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having separable energized conducting parts normally carrying line current and shunted by an auxiliary circuit interrupter to permit separation of said parts without arcing therebetween, one of said parts being relatively stationary and the other being movable away therefrom, and a conducting member on each of said parts detachably receiving said auxiliary circuit interrupter, the con ducting member on said one part extending transversely of the plane of movement of the other part.

7. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having separable energized conducting parts normally carrying line current and shunted by a separable contact type of auxiliary circuit interrupter to permit separation of said parts without arcing therebetween and subsequent opening of the circuit by separation of the contacts of said auxiliary circuit interrupter, one of said separable conducting parts being relatively stationary and the other being carried at one end of a rigid elongated member, means pivotally mounting the other end of said elongated member, cooperating pin and eye means on said auxiliary circuit interrupter and on said one conducting part detachably receiving the former on the latter and resisting an endwise pull on said auxiliary circuit interrupter for operating it to open the circuit and adapted to receive it from various angles in planes at right angles to each other, and additional cooperating pin and eye means on said auxiliary circuit interrupter and on said other conducting part detachably receiving the former on the latter and movable therewith for moving said elongated member from closed position.

References Cited in the file of this patent UNITED STATES PATENTS 532,594 Scott et al Jan. 15, 1895 1,393,344 Conrad Oct. 11, 1921 2,174,476 Pittman et al. Sept. 26, 1939 2,263,513 Meyer Nov. 18, 1941 2,310,466 Schultz et al. Feb. 9, 1943 2,327,865 Brown et a1 Aug. 24, 1943 2,348,029 Smith May 2, 1944 2,351,826 Lindell et a1 June 20, 1944 2,521,155 Earle et a1. Sept. 5, 1950 2,548,129 Steinmayer Apr. 10, 1951 2,621,271 Lindell Dec. 9, 1952 2,621,272 Kojis Dec. 9, 1952 2,629,794 Hubbard et al Feb. 24, 1953 2,709,736 Schneider May 31, 1955 2,716,681 Smith Aug. 30, 1955