US3349200A

US3349200A - Power line contact for disconnect switch

Info

Publication number: US3349200A
Application number: US506045A
Authority: US
Inventors: Crepel Jean; Zacar Alain
Original assignee: Compagnie Generale dElectricite SA
Current assignee: Alcatel Lucent SAS
Priority date: 1965-02-10
Filing date: 1965-11-02
Publication date: 1967-10-24
Anticipated expiration: 1984-10-24
Also published as: ES319144A1; FR1438297A

Description

1957 J. CREPEL ETAL POWER LINE CONTACT FOR DISCONNECT SWITCH 3 Sheets-Sheet l FIG.2

Filed Nov. 2, I 1965 IVVEMTOU \TEAN Gee-Pa 401M! 240m Filed Nov. 2, 1965 POWER LINE CONTACT FOR DISCONNECT SWITCH 3 Sheets-Sheet 2 FIG. 4 23 FIGS IIVVEA TOPS J64 Gee/ 54 4mm 2 A 6 19/8 Oct. 24, 1967 I J. CREPEL ETAL 3,349,200

POWER LINE CONTACT FOR D ISCONNECT SWITCH Filed Nov. 2, 1965 FIG.6 FIG.8

3-Sheets-Sheet 3 3 l/VVE/VTO/ES JEAW 6261 61.

4mm zacne Y 2 2, Q4

1977-0 MEY United States Patent 5,005 19 Claims. (Cl. 200-48) ABSTRACT OF THE DISCLOSURE A suspension device for an overhead power line contact for a vertically moving disconnect switch in the form of a polygon of articulated links, such as a pentagon arrangement, capable of confining the movement of said contact to a single vertical plane even during displacement of the power line to a great extent and which may include spring means to limit the extent of movement of the contact.

The present invention relates ingeneral to disconnect switches for use on high voltage systems and more particularly to a power line contact and suspension device therefor to be used in combination with a disconnect switch not only to improve the operation of the switch but also to make possible a more efiicient design thereof.

Disconnect switches of known type consist generally of a pantograph type switch mechanism mounted upon insulating pillars and having a movement from a lower, retracted open position vertically to a raised, extended closed position wherein electrical contact is made by the upper end of the extendable switch mechanism with an overhead conductor or bus-bar. One of the major problems involved with such switch is that the elements need to be constructed in such a manner that the contacts will be certain to close in a positive manner. This raises questions of contact pressure as well as the various possible positions of the overhead contact.

It is known that the overhead power line conductors are subjected to significant displacements on both sides of the position of rest thereof under the action of exterior forces, particularly under the action of wind and electrodynamic stresses. The contact bar which cooperates with the jaws of the disconnect switch to some extent follows these displacements and exerts considerable stresses upon the disconnect switch. For this reason, such switches have had to be designed to withstand the great stresses and'to be capable of acquiring the contact bar at any position within a rather large area. This latter requirement necessitates a rather large displacement of the contact bar between positions of closing and opening of the switch. On the other hand, the more significant the displacement of the contact bar becomes between the positions of closing and opening of the disconnect switch, the more will the amount of the separation in the open position be reduced.

The present invention therefore has the object of maintaining the displacements of the contact bar at all times essentially in a common vertical plane and of reducing the amplitude thereof between the movements of closing and of opening of the disconnect switch. As a result of the reduction of the stresses which act upon the disconnect switch, the construction of the latter may, accordingly, be made lighter.

The present invention is directed to a suspension device for an overhead power line contact for a disconnect switch having vertical movement which is characterized in that the contact bar which cooperates with the jaws of the 3,349,200 Patented Oct. 24, 1967 disconnect switch is connected at the ends thereof with a pair of cross bars mounted on the conductor or conductors of the line by a suspension device in the form of a polygon capable of being deformed in response to movements of said conductors. The two sides of the suspension device terminating at the contact bar are articulated therewith and in cooperation with the movable part of the disconnect switch assure, during the operations of opening and closing, the displacement of the bar essentially in the same vertical plane so as to allow for a great amount of displacement of the power line conductors under the action of exterior forces without producing or giving rise to an abnormal stress on the bar or the movable part of the disconnect switch.

According to a further embodiment of the present invention, the vertical displacement of the bar may be controlled by the interposition of an elastic element in the suspension device which limits the lowest position of this bar.

It is an object of the present invention to provide a suspension device for the contact bar of a disconnect switch of the pantograph type in the form of a polygon capable due to its configuration of substantially completely absorbing the exterior stresses on the contact bar due to displacement of the electrical lines.

It is another object of the instant invention to provide a suspension device of the type disclosed wherein the closed position of the switch, whatever be the displacement of the power line conductors, the contact bar will experience only insignificant forces.

These and other objects, features and advantages of the invention will become more apparent from the following specific description of the invention when taken with the accompanying drawings, wherein:

FIGURE 1 is an elevational view of a power line suspension device according to the present invention, viewed in the direction of the power line conductors;

FIGUREVZ is a schematic perspective view at a smaller scale of the suspension device of FIGURE 1 with associated disconnect switch; I

FIGURE 3 is a schematic view showing the position of the different elements of the suspension device of FIGURE 1, on the one hand in the position of opening and, on the other hand, in the position of closing when the line is displaced;

FIGURE 4 is an elevational view, as seen in the direction of the power line conductors, of an embodiment which makes it possible to limit the displacement of the contact bar between the two extreme positions of the disconnect switch;

FIGURE 5 is a schematic view showing the position of the different elements of the suspension device of FIG- URE 4, on the one hand in the position of opening, and on the other hand, in the position of closing when the line is displaced, and

FIGURES 6 through 10 are schematic views of different embodiments of the device of FIGURE 5, when viewed in the direction of the power line conductors.

In the drawings and in the [following description thereof, a line has been chosen as example which comprises two conductors carrying voltages of differing phase since the suspension device according to the present invention is particularly suitable for this type of line. But all the elemerits of the present invention are equally applicable to lines comprising either only a single or more than two phase conductors.

In FIGURES l and 2, the power line conductors are represented at 1 and 2 in the normal position of rest thereof in the absence of exterior stresses. The contact bar 3, which cooperates with the jaws of a disconnect switch of any conventional configuration for example of thepantographtype, is suspended on the line conductors 1 and 2 at the extremities 4 and 5 thereof by means of two cross bars 6 and 6' and by two groups of articulated rods, one

group including rods

7, 8, 9, (FIGURE 1) suspended from the cross bar 6 and the other identical group being suspended at the cross bar 6' of FIGURE 2. Each cross bar is thus connected to the contact bar by a suspension device in the form of a symmetrical pentagon in the position of rest with the sides formed by

small rods

8 and 10 being shorter than the sides formed by

rods

7 and 9. The

rods

7 and 9 are articulated on the one hand at the

ends

11 and 12 of the cross bar 6 and on the other hand at 13 and 14 to the

small rods

8 and 10,'abutting respectively on the

rods

7 and 9. The

rods

8 and 10 are, in turn, articulated at 15 and 16 to the clamping piece 17 supporting one end of the contact bar 3. Cables or

wires

18 and 19 are disposed along the rods and provide an electric connection between the power line conductors 1 and 2 and the contact bar 3. In addition, abutments Sa-and 10a may be provided to limit the lower position of the contact bar 3.

In FIGURE 2, when the disconnecting switch is open, as illustrated, and the line is not subjected to exterior stresses, the contact bar is situated in the lower position of rest 3 thereof under the action of its weight. The power line conductors, the cross bar and the rods occupy, re-

spectively, the

positions

1, 2, 6, 7, 8, 9 and 10. At the time of closing of the disconnect switch, the jaws of the switch seize the bar and bring it from the position 3' vertically into the position 20 (FIGURE 3) and, at the end of the closing operation the power line conductors, the cross bar and the small rods occupy the

positions

1, 2, 6,7, 21, 9, 22. This ascending course of the bar during the closing operation allows the power line conductors to be displaced toward the right or toward the left under the action of exterior forces while causing vir-' tually no displacement of the contact bar, which remains in an essentially fixed position at 20. The line, the cross bar and the small rods may occupy, respectively, any position between the two extremes 1', 2', 6, 7', 21', 9', 22' at. the right, and 1", 2", 6", 7", 21", 9", 22 at the left, without causing any significant displacement of the contact bar.

In this provision, as in the embodiments which will be described hereinafter and which are represented in FIG- URES 4 through 10, the displacementof the power line conductors exerts, by means of the small rods, a slight traction on the contact bar in the position of closing and, as a result of the. elasticity of the parts, causes a slight displacement of this bar, but this displacement remains at all times a very small fraction of the displacement of the power line conductors 1 and 2.

The advantageous feature of the present invention results from the fact that in the position of closure of the disconnect switch, a very greatdisplaccment of the power line conductors is permitted without producing an importanteffect on the contact bar and thus on the switch itself. This advantage is derived primarily from the configuration of the suspension devicewhich is flexible to the extent that movement of the cross bar 6 will not produce a corresponding movement of the contact bar.

However, the arrangement or provision of FIGURES 1, 2 and 3 has the following drawback: the maximum extent of the ascending course of the contact .bar which would be strictly necessary to allow for a sufficient displacement of the power line conductors from 1', 2' to 1", 2" is not nearly so great as the course 3-20 shown in FIG- URE 3; however, the lowest position 3 of the contact bar in the position of opening of the disconnect switch is defined by the position of equilibrium thereof under the action of gravity of the total structure of the bar 3 and the rods which make of the suspension device. Besides, as shown in FIGURE 3, in view of the various positions of the rods necessary to effect the displacements at 1, 2' and -1 and 2" due to movements of the line when the disconnect switch is closed, it is not possible to more completely limit the downward displacement of the

rods

8 and 10 by means of abutments so as to limit the descent of the bar 3 when the disconnect switch is open without raising problems of interference. A significant displacement 3-20 has the inconvenience of reducing by the same extent the distance of opening of the disconnect switch and consequently of requiring a greater course of the movable part of the latter.

In accordance with the present invention, it is preferable to limit the course or extent of movement of the contact bar to a minimum compatible with a suflicient displacement of the power line conductors by no longer allowing the lowest position of the contact bar in the open position of the disconnect switch to be determined by gravity alone, but to fix this position in accordance ,with.

the combined effect of gravity and of an elastic element, such as a spring. The latter acts on the contact bar in an inverse sense 0d direction opposite that of gravity when the disconnect switch isin the open position and prevents the bar from assuming an unnecessarily low position. On the other hand, when the disconnect switch is in the closed position and when the line is displaced, the spring acts in such a manner as to exert only a slight stress on the bar so as to reduce the strains on the movable part of the disconnect switch. FIGURE 4 shows an embodiment of the invention which provides such a feature.

In FIGURE 4, as in FIGURE 1, the line contact comprises two cross bars 6 secured to the power line conductors 1 and 2, small rods such as 7, 8, 9, 10 articulated at 11, 12, 13 and 14 as well as at 23 to a piece or support element 17 supporting one of the extremities of the contact bar 3 whose electrical connection with the power line conductors 1 and 2 is assured by suitable cables or wires such as 18 and 19. A spring .24 guided and protected l against ice is provided for each group of four

rods

7, 8,

9 and 10, which spring is articulated on the one hand at i 23 on the element 17 by means of an abutting rod 25, and on the other hand, in a swivel joint 26- with the aid of a second abutting rod 27 whose extremity 28 protected against ice by a cover 29 rests on the cross bar 6 when the disconnect. switch is in the open position, with the contact bar 3 in the lower position thereof (FIGURE 4).

FIGURE 5 shows the elements of the line contact; power line conductor, contact bar, cross bar, small rods,

respectively. In the absence of exterior forces and in the open position of the disconnect switch, the elements take positions at 1, 2, 20, 6, 30, 21, 31, 22. When the power line conductors, 1 and 2 are displaced toward the right under the action of exterior forces, the. disconnect switch being in the closed position, the elements. move to posi-' tions at 1', 2', 6, 30, 21, 31, 22',

When, in the absence of exterior forces, the disconnect switch passes from the open to the closed position, the extremity of the upper abutting rod 27 of the spring 24 is lifted, as at 32, above the cross bar 6. A major displace' ment of the conductors due to exterior forces with'the switch in the closed position tforcesthe extremity of the.

rod 27 to abut at 32' with the swivel joint 26 of the cross bar 6. The spring 24 which elastically connects the two abutting

rods

25 and 27 is stretched according to 24', thereby causing the separation of the two

rods

25 and 27, for example at the upper portion of the spring 24, and exerts a slight stress in tractiomon the contact bar at 20.

FIGURE '6 through 10 show diflferent embodiments or arrangements of the suspension device of FIGURE 4. The elements of these embodiments which are identical to the constructions of FIGURES 1 to 5 have been identified .with corresponding reference numerals wherever.

possible. FIGURES 6 through 10 differ from FIGURES resent is analogous to that of FIGURE 4.

In FIGURE 6 is a draw-spring 33 utilized and in FIG- URE 7 a compression spring, permanently secured to the joint 13 and allowing for a free displacement of the joint 14 at the time of closing, is utilized. In FIGURE 8, the

rods

7 and 9 are elongated, respectively, at 35 and at 36 beyond the

articulations

11 and 12 on the cross bar 6 and a spring 34 placed above the power line conductors 1 and 2 exerts a tractive force on the extremities of the

elongated portions

35 and 36 of the

rods

7 and 9, all of this being provided for the purpose of allowing for the raising of the conductor 3 at the time of closing Olf the disconnect switch.

In FIGURE 9, torsion springs 38 and 39 are utilized whose one

extremity

40 and 41, respectively, is integral with the

rods

7 and 9 articulated at 13 and 14 and whose

other extremity

42 and 43, respectively, is integral with the cross-bar 6 being secured to the power line conductors 1 and 2. The emboidment shown in FIGURE is analogous to that of FIGURE 4, but the single spring 24 of FIGURE 4 is replaced by two springs 44 and 45, which are articulated, on the one hand, on the piece supporting the contact bar 3 and, on the other hand, are respectively slidingly supported in the swivel joints 11 and 12.

As has been set forth hereina'bove, such a line suspension device may be utilized in conjunction with a disconnect switch of the pantograph type having a light construction and having short contact jaws, particularly with the one described in the French patent application entitled, Disconnecting Switch Having Vertical Movement, filed on Feb. 4, 1965, in the name of applicant.

While we have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art; and we therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as 1 are encompassed by the scope of the appended claims.

We claim:

1. Suspension device for supporting the contact bar of a pantograph type disconnect switch from a pair of high voltage conductors comprising:

a polygon arrangement for supporting each end of said contact bar, each including a crossbar mounted on said high voltage conductors transversely thereto and a plurality of articulated side members interconnecting said crossbar to one end of said contact bar,

said contact bar being supported by said polygon arrangements essentially parallel to said conductors and in the vertical plane of operation of said disconnect switch,

said polygon arrangement being deformable in such a manner that in the closed position of said disconnect switch with said contact bar shifted vertically, each of said side members connected to said contact bar being capable of freely rotating in response to displacements of said conductors.

2. Suspension device as claimed in claim 1 wherein each polygon arrangement being constituted of small rods mutually articulated at the extremeties of the corresponding crossbar and on a side member forming the support of the corresponding extremety of the contact bar.

3. Suspension device as claimed in claim 2 further including means for limiting the distance between said crossbar and said contact bar in the open position of said disconnect switch in opposition to the force of gravity.

4. Suspension device for supporting the contact bar of a pantograph type disconnect switch from a pair of high voltage conductors comprising;

a five-sided flexible arrangement for supporting each end of said contact bar each including in the open condition of said disconnect switch a crossbar securely mounted on said high voltage conductors transversely thereto, a first pair of substantially vertically disposed side members articulated at one end to opposite sides of said crossbar, a second pair of side members each articulated to the other end of a respective one of said first pair of side members and articulated at the other end thereof to an end of said contact bar,

said contact bar being supported by said flexible arrangements essentially parallel to said conductors and in the vertical plane of operation of said disconnect switch,

said flexible arrangement being deformable in such a manner that in the closed position of said disconnect switch with said contact bar shifted vertically, each of said second pair of sides is capable of freely rotating in response to displacements of said conductors.

5. Suspension device as defined in claim 4 wherein said second pair of side members being of shorter length than said first pair of side members.

6. Suspension device as claimed in claim 5 and further including a clamping piece securely connected to each end of said contact bar and each articulated to a respective flexible arrangement.

7. Suspension device for supporting the contact bar of a pantograph type disconnect switch from a pair of high voltage conductors comprising;

five rods articulated end-to-end in a pentagon arrangement, one of said rods serving as a crossbar securely mounted on said high voltage conductors transversely thereto,

said contact bar being supported essentially parallel to said conductors by a pentagon arrangement articulated at each end thereof.

8. Suspension device as claimed in claim 7 and further including spring means for limiting the distance between said crossbar and said contact bar in the open position of said disconnect switch in opposition to the force of gravity.

9. Suspension device as claimed in claim 8 and wherein said spring means is secured between said rod serving as a crossbar and said contact bar.

10. Suspension device as claimed in claim 9 and wherein said spring means is in the form of a draw spring connected between points of articulation of said rods between said crossbar and said contact bar.

11. Suspension device as claimed in claim 9 and further including said spring means being in the form of a compression spring connected between extensions on the rods articulated to said crossbar.

12. Suspension device as claimed in claim 8 wherein said spring means is in the form of a compression spring connected between points of articulation of said rods between said crossbar and said contact bar. 7

13. Suspension device as claimed in claim 8 and wherein said spring means is in the form of a torsion spring integral with the rods directly articulated to said crossbar.

14. Suspension device as claimed in claim 8 and wherein said spring means includes a pair of springs each connected at one endto said contact bar and having the other ends thereof connected to the ends of said crossbar, respectively.

15. Suspension device for supporting the contact bar of a pantograph type disconnect switch from a pair of high voltage conductors comprising;

at least one flexible pentagon arrangement of support members secured between said contact bar and said conductors;

means for limiting the distance between said crossbar and said contact bar in the open position of said disconnect switch in opposition to the force of gravity.

16. Suspension device as claimed in claim 15 and wherein said means for limiting the distance between said crossbar and said contact bar is in the form of a spring interconnecting opposing portions of said pentagon arrangement.

7 8 17. Suspension device as claimed in claim 16 wherein References Cited said spring has stop-limits regulating the extent of expan- UNITED STATES PATENTS sion thereof.

18. Suspension device as claimed in claim 17 wherein 21766541 said means for limiting the distance between said crossbar FOREIGN PATENTS and said contact bar includes an ice shield for said spring.

19. Suspension device as claimed in claim 15 and 1O74903 12/1958 Germany wherein said means for limiting the distance between said ROBERT K SCHAEFER Primar Examiner crossbar and said contact bar is provided as abutments y formed as extensions of two of said support members. 10 HOHAUSER, Assistant Examine!- 10/1956 Haller 200-48

Claims

7. SUSPENSION DEVICE FOR SUPPORTING THE CONTACT BAR OF A PANTOGRAPH TYPE DISCONNECT SWITCH A PAIR OF HIGH VOLTAGE CONDUCTORS COMPRISING; FIVE RODS ARTICULATED END-TO-END IN A PEN ARRANGEMENT, ONE OF SAID RODS SERVING AS A CROSS BAR SECURELY MOUNTED ON SAID HIGH VOLTAGE CONDUCTORS TRANSVERSELY THERETO, SAID CONTACT BAR BEING SUPPORTED ESSENTIALLY PARALLEL TO SAID CONDUCTORS BY A PENTAGON ARRANGEMENT ARTICULATED AT EACH END THEREOF.