US2486143A - Electrical cutout - Google Patents

Description

Oct. 25, 1949.. c. A. FOX 2,486,143

ELECTRICAL CUTOUT Filed May 9, 1946 2 Sheets-Sheet 1 /lvl/.A/7?s& CHARLES ADIN Fox @Qfi 25 c, A zy'gfiglfs ELECTRICAL CUTOUT Filed May 9, 1946 2 Sheet-Sheet 2 CHARLES Aom Fox Patented Oct. 25, 1949 ELECTRICAL CUTOUT Charles Adin Fox, Oakland Village, Mo., assignor to James R. Kearney Corporation, St. Louis, Mo., a corporation of Missouri Application May 9, 1946, Serial No. 668,376

10 Claims.

This invention relates generally to electrical cutouts, and more specifically to electrical cutouts of the type disclosed in United States Letters Patent No. 2,086,028, granted to Walter A. Heinrich and Charles Adin Fox, on July 6, 1937, and which includes a relatively fixed contact arm and a downwardly swingable contact arm between which a fusible element is disposed which is adapted to be ruptured as a result of passage of abnormal electrical current therethrough to interrupt the electrical circuit with which the cutout is electrically associated, the predominant object of the invention being to provide an electrical cutout of the type mentioned which includes contact arms of such improved construction and arrangement that the improved cutout may be employed in electrical association with electrical circuits carrying currents of higher amperages.

Another important object of the invention is to provide an electrical cutout of the type referred to above which includes improved shunt means for conducting electrical current from a terminal of the cutout to the swingable contact arm thereof.

Fig. 1 is a side elevational view of the improved cutout of the present invention.

Fig. 2 is a horizontal section taken on line 2-2 of Fig. 1.

Fig. 3 is an enlarged, fragmentary, vertical section taken on line 3-3 of Fig. 1.

Fig. 4 is an enlarged, vertical section taken on line 44 of Fig. 1.

Fig. 5 is a horizontal section taken on line 55 of Fig. 1.

Fig. 6 is a fragmentary, vertical section taken on line 6@ of Fig. 5.

In the drawings, wherein is shown for purposes of illustration, merely, one embodiment of the invention, A designates the improved cutout generally. The cutout A includes a suitable insulator I formed of porcelain, or other suitable electrical insulating material, to which is secured a suitable bracket 2 that aids in the attachment of the cutout to a pole crossarm, or other support.

Supported by the insulator I at the upper end thereof is an upper terminal 3 which is formed of electrical conducting material and includes a segmental cap portion 4 that embraces a part of the upper portion of the insulator I, as is shown in Fig. 1. At its opposite sides the cap portion 4 of the upper insulator 3 is provided with outstanding apertured lugs 5 (Fig. 2) through which end portions of a U-shaped rod 6 are extended, said rod being drawn into embracing relation with respect to a part of the upper portion of tions I6 (see Fig. 2).

the insulator I by nuts I which are applied to the outer end portions of the rod and forcibly engage the lugs 5 so as to securely clamp the upper terminal 3 to said insulator I. The upper terminal -3 includes, also, a head portion 8 which is formed integral with the segmental cap portion 4, and extended upwardly from said head portion is an extension 9, said extension having electrically and mechanically attached thereto, by means of a suitable connector III, a conductor Ca, which forms a part of the electrical circuit with which the cutout A is electrically associated. The segmental cap portion 4 has formed thereon a lug 4 which is provided with a horizontal top face, as is shown in Fig. 1.

Secured to and extended outwardly from the upper terminal 3 is an upper contact arm II. The upper contact arm II is comprised of a pair of contact arm members Ila and II?) which are duplicates, said contact arm members being arranged in parallelism, one above the other, and in close contact with each other, as shown in Fig. 1. When viewed in plan, as is shown in Fig. 2, each of the contact arm members Ila and Ill) comprises a pair of transversely spaced, forwardly extended arm portions I2 which are joined at the inner ends by a curved arm portion I3 so as to provide a loop at the inner end of each contact arm member, the contact arm members Ila and III) being secured to the upper terminal 3 at the horizontal top face of the lug 4' thereof by a bolt I4 which extends through a washer I5, and through the loops at the rear ends of both of the contact arm members, and is screwed into a screwthreaded opening formed in the lug 4' of the upper terminal 3.

The contact arm members Ila and Nb are formed of material which is inherently resilient and which is a good conductor of electrical current, the forwardly extended, spaced portions I2 of each of said contact arm members being provided with portions I6 which are bent rearwardly in contact with forward portions of said portions I2, and portions I! which extend outwardly and rearwardly from the rear ends of said por- At the forward ends of the contact arm members Ila and III) a sleeve I8 is provided which includes opposite side portions I8 that embrace parts of the portions I2 and I6 of the contact arm members Ila and III), and portions I8" which join said embracing portions I8, as is shown in Fig. 4, said sleeve serving to retain the forward portions of said arm portions in their proper related positions.

Supported by the lower portion of the insulator secured to its lower end portion by means of a suitable connector 23 an electrical conductor Cb which comprises a part of the electrical circuit with which the cutout A is electrically associated.

The member 20 which comprises the lower terminal [3 of the cutout A supports a lower contact arm 24, said contact arm including a contact arm member 24a which is formed from a single, continuous length of heavy wire which is inherently resilient. The contact arm member 24a has formed therein a pair of spaced coiled portions 25, and extended rearwardly from the centers of said coiled portions are opposed portions 26 which are continuations of the coiled portions and which merge at their rear ends into an upwardly extended loop portion 21 that contacts with the forward face of the lower terminal member 20 (Figs. 1 and 5). The lower contact arm 24 is secured to the lower terminal member by means of a bolt and nut assembly 28, the shank portion of the bolt being passed through the loop 21 and through an opening formed through said lower terminal member 20.

Extended outwardly from the outer, lower portion-s of the coiled portions of the lower contact arm 24, as continuations of said coiled portions, is a pair of transversely spaced, parallel contact arm portions 29. These portions 23 are retained in their proper spaced relation by a spacing element which is preferably formed of sheet metal, said spacing element having opposed edge portions that closely embrace the spaced, lower contact arm portions 29, and a connecting portion which joins said opposed embracing portions (Fig. 5). Extended from the lower contact arm portions 23 as integral eontinuations thereof are convergent lower contact arm portions 3|, and these portions 3! merge into forwardly extended, transversely spaced, parallel contact arm i portions 32. At their forward ends the contact arm portions 32 are provided with rearwardly bent portions 33 which contact with forward portions of said contact arm portions 32, said rearwardly bent portions 33 being provided at their rear ends with outwardly and rearwardly extended, angular portions 34.

The lower contact arm includes, also, a contact arm member 241) which comprises a length of heavy wire shaped to provide a pair of elongated, parallel portions 35. At the rear ends of said portions the contact arm member 24b is provided with a loop 36, and at th forward end of said portions 35 the contact arm member 241) is provided with rearwardly bent portions 33 and outwardly and rearwardly extended, angular portions 34 similar to the corresponding and similarly designated parts at the outer end of the contact arm member 24a. The rear end portion of the contact arm member 24b is secured to the spacing element 30 by a bolt and nut assembly 37, as is shown to good advantage in Fig. 6, the shank portion of the bolt of said assembly being extended through the loop of said contact arm member 24b and through an opening formed through a portion of the spacing element 30. Forward parts of the portions 35 of the contact arm member 241) contact with the portions 32 of contact arm member 24a, and the forward portion of the contact arm member 24b which is made up of the portions 33 and 34 contact with corresponding portions of the contact arm member 24a.

Th forwardly extended, transversely spaced portions 32 and 35 of the contact arm members 24a and 24b are secured together and are maintained in their proper spaced relation by an element 38 which is provided with opposed portions which embrace said contact arm portions, and a portion which joins said embracing portions.

to the member 20 which comprises the lower terminal of the cutout. This shunt structure comprises an element 40 which includes a pair of transversely spaced, forwardly extended portions 4| that are joined at their forward ends by an integral, transversely extended portion 42. Also, at the rear ends of said transversely spaced, for- Wardly extended portions 4|, said element 40 is provided with an upwardly extended, integral loop portion 42, through which the shank portion of the bolt of the previously mentioned bolt and nut assembly 28 is extended for securing said element 40 to the member 20 that comprises the lower terminal of the cutout A, a washer 43 being interposed between the loop portion 42' of the element 40 and the loop portion 21 of the lower contact member 24a (Figs. 1 and 5). The shunt structure includes, also a strip of material 44 which, like the element 40, is a good conductor of electrical current, said strip of material being soldered, or otherwise secured, at its inner end to the transverse portion 42 at the forward end of the element 40, and being coiled about said transverse portion. Th strip of material 44 of the shunt structure includes a portion 45 which extends forwardly from the coiled portion thereof, and this forwardly extended strip portion is secured by the previously mentioned bolt 31 to the spacing element 30 of the lower contact arm 24 of the cutout A.

The cutout A includes a fuse link F which comprises a pair of flexible cables 46 and 4! that are provided at their outer ends with suitable eyes 46' and 41'. The cables 46 and 41 are spaced apart at their inner ends, and arranged in mechanical and electrical connection with said cables and disposed in the space between the spaced inner ends of said cables is a fusible element 48. The space between the inner ends of the cables 46 and 41 and the fusible element 48, together with inner end portions of the cables, are embraced by a tube 49 which is formed of suitable electrical insulating material, said tube 49 being suitably maintained in its assembled relation with respect to the cables 46 and 41 of the fuse link to provide a unitary fuse link structure.

To assemble the fuse link F with the cutout, a portion of the cable 41 of said fuse link is drawn fuse link. With the finger of the stick still in engagement with the eye 46' of the fuse link, said fuse link is moved upwardly toward the upper contact arm H thereby moving the outer end portion of the lower contact arm 2 from the lowered position in which it is shown by dotted lines in Fig. l to the position in which said lower contact arm is shown by full lines in Fig. 1. When the fuse link has been elevated to the proper degree a portion of the cable 46 is drawn deep into one or the other of the crotches of the upper contact arm H which are provided by the rearwardly bent portions l5 and adjacent portions 12 of said upper contact arm. The finger of the stick is then disengaged from the eye 46' of the fuse link and the cutout is in a fused condition and is ready for use.

When, in the use of the improved cutout, a fault occurs in the circuit with which the cutout is associated which is of a character to blow the fuse link, the fusible element #8 of the fuse link will be ruptured. This will free the lower contact arm from the restraint imposed thereon by the unruptured fuse link with the result that the coiled portions of the lower contact arm 24,

in which energy was stored when the outer end portion of said lower contact arm was moved upwardly in applying the fuse link, will move the outer end portion of the lower contact arm rapidly in a downwardly extended arc of a circle to the approximate position in which said lower contact arm is shown by dotted lines in Fig. l. The described downward movement of the outer end portion of the lower contact arm 24 will quickly pull the ruptured ends of the fusible element 48 of the fuse link F apart, whereby an electrical arc formed between said ruptured ends of said fusible element will be extinguished within the tube as of the fuse link.

It is important to note that because the lower contact arm 24 is composed of a pair of contact arm' members 24a and 241), such adequate gripping of the fuse link cable A! by the lower contact arm is obtained as will insure efficient operation of the cutout with circiuts carrying higher amperages, this being true because the cable l! of the fuse link is gripped by both of the contact'arm members of which the lower contact arm is comprised. The above is true also of the upper contact arm H as said upper contact arm is composed of a pair of contact arm members, both of which grip the cable 46 of the fuse link. Also, it is to be noted that while the outer portion of the lower contact arm 24 is composed of a pair of contact arm members 24a and 24b which both grip the cable M of the fuse link, yet the spaced, coiled portions 25 of the lower contact arm are parts of only one of said contact members, that is, the contact member 24a. Because of this arrangement the lower contact arm is provided with the required resiliency for rapid downward movement when the fuse link is ruptured, which would not be the case if heavier material were employed in the production of a lower contact arm that would grip the fuse link cable to the degree required for higher amperages.

I claim:

1. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms being movable in a direction away from the other contact arm, and a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said one contact arm to move in a direction away from the other contact arm, said one contact arm being composed in part of a pair of structurally distinct contact arm members having fuse link gripping portions which engage said fuse link.

2. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portionto give increased resiliency thereto and being movable in a direction away from the other contact arm, and a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm, said contact arm of increased resiliency being composed in part of a pair of structurally distinct contact arm members having parts arranged one above the other and provided with fuse link gripping portions which engage said fuse link.

3. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm, said contact arm of increased resiliency being composed in part of a pair of structurally distinct contact arm members having parts arranged one above the other and provided with fuse link gripping portions which engage said fuse link, and means for securing together said pair of contact arm members of said contact arm of increased resiliency.

l. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, and a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm, said contact arm of increased resiliency having a portion which is located forwardly of the coiled portion thereof that is composed of a pair of structurally distinct contact arm members which engage said fuse link.

5. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, and a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm,

said contact arm of increased resiliency having a portion which is located forwardly of the coiled portion thereof that is composed of a pair of structurally distinct contact arm members having parts arranged one above the other which engage said fuse link.

6, An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, a fuse link engaged by portions of said contact arms and maintained under tension While in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm, said contact arm of increased resiliency having a portion which is located forwardly of the coiled portion thereof that is composed of a pair of structurally distinct contact arm members having parts arranged one above the other and provided with fuse link gripping portions which engage said fuse link, and means for securing together said pair of contact arm members of said contact arm of increased resiliency.

'7. An electrical cutout comprisin an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm, said contact arm of increased resiliency having a portion which is located forwardly of the coiled por tion thereof that is composed of a pair of structurally distinct contact arm members which engage said fuse link, and a shunt structure for conducting electrical current directly from one of said terminals to the portion of said contact arm of increased resiliency which is composed of a pair of contact arm members.

8. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of arm of increased resiliency which is composed of a pair of contact arm members, said shunt structure including a strip of electrical conducting material having a coiled portion.

9. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms havin a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm, said contact arm of increased resiliency having a portion which is located forwardly of the coiled portion thereof that is composed of a pair of strucdurally distinct contact arm members which engage said fuse .link and a shunt structure for conducting electrical current directly from one of said terminals to the portion of contact arm of increased resiliency which is composed of a pair of contact arm members, said shunt structure including a supporting element which is secured to the terminal with which the shunt structure is associated, and a strip of electrical conducting material that is coiled about a part of said supporting element and which includes a portion extended from the coiled portion of said strip of material which is secured to said forwardly located portion of said contact arm of increased resiliency.

10. An electrical cutout comprising an insulating supporting structure including spaced terminals, contact arms associated with said terminals, one of said contact arms having a coiled portion to give increased resiliency thereto and being movable in a direction away from the other contact arm, and a fuse link engaged by portions of said contact arms and maintained under tension while in the fusing position by the tendency of said contact arm of increased resiliency to move in a direction away from the other contact arm, said contact arm of increased resiliency being composed in part of a pair of structurally distinct contact arm members and the other of said contact arms being composed of a pair of structurally distinct contact arm members and portions of said fuse link being engaged by both of the contact arm members of the respective contact arms.

CHARLES ADIN FOX.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 657,414 Hundhausen Sept. 4, 1900 2,086,028 Heinrich et a1. July 5, 1937 2,304,250 Fox Dec. 8, 1942

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