US2779830A

US2779830A - High voltage switch

Info

Publication number: US2779830A
Application number: US399316A
Authority: US
Inventors: John L Turner; Frederick J Krummel
Original assignee: Turner Electric Corp
Current assignee: Turner Electric Corp
Priority date: 1953-12-21
Filing date: 1953-12-21
Publication date: 1957-01-29
Anticipated expiration: 1974-01-29

Description

1957 .1. L. TURNER ETAL ,77

HIGH VOLTAGE SWITCH 2 Shets-Sheet 1 Filed Dec. 21, 1953 INVENTOR. Kf'

Jan. 29, 1957 J. L. TURNER ETAL 2,779,830

HIGH VOLTAGE SWITCH Filed Dec. 21, 1955 2 Sheets-Sheet 2 9 43 b 46 Flow 44' 9 45 2 FIG-.9

INVENTOR.

MXJ/mwc/ era United States Patent HIGH VOLTAGE SWITCH John L. Turner and Frederick J. Krummel, East t. Louis, 111., assignors to Turner Electric Corporation, East St. Louis, 111., a corporation of Illinois Application December 21, 1953, Serial No. 399,316 11 Claims. (Cl. 200-48) This invention relates in general to high voltage switches and, more particularly, to air break switches of the type utilized for isolation or sectionalization and for disconnection to interrupt exciting currents and light transformer loads.

A primary object of this invention is to provide an air break switch which incorporates a switch blade adapted for pivotal movement about a point between its ends, and means for maintaining one end of the blade in conductive engagement with one stationary terminal irrespective of the functioning of the opposite end of the blade.

Another object is to provide spaced, resilient arcing horns in axial parallel relation to, and mounted on, the

switch blade, and adapted for maintaining current flow until the switch blade, in opening, has been moved from cooperating contacts a distance sufficient to prevent arc restriking between the blade and the contacts.

An additional object is to provide a switch blade adapted for axial rotative movement and carrying a noncircular contact element on one end for reception be tween contacts, and means for rotating said blade in the initial closing and initial opening movement for efiective switch opening and closure with high pressure creating engagement between the blade and the contacts.

A further object is to provide a swinging switch blade with contact elements on both ends adapted for high contact pressure-creating engagement between cooperating contact members, whereby a cleansing or Wiping action is etfected on the surfaces of said contact members to assure maximum conductivity.

A further object is to provide an air break switch which is simple in construction, durable and reliable in operation, and which may be economically manufactured.

These and other detailed objects are attained by the structure illustrated in the accompanying drawings, in which:

Figure 1 is an elevational view of a high voltage air break switch embodying the present invention and showing the same in circuit closing position. Parts of the switch are broken away to make the drawing on a larger scale.

Figure 2 is a vertical transverse section taken on line 2-2 of Figure 1.

Figure 3 is a vertical transverse section taken on the line 3-3 of Figure 1.

Figure 4 is a horizontal transverse section taken on the line 4-4 of Figure 1. r

Figure 5 is a vertical transverse section taken on the line 5-5 of Figure 4. j

Figure 6 is a vertical transverse section taken sub stantially on the line 22 of Figure 1, illustrating the switch blade rotated axially to shift its contact element into position for switch-opening operation.

Figure 7 is a top view of the switch in circuit opening and opened position. Parts are omitted as in Figure 1.

Figure 8 is a vertical transverse section taken on the line 88 of Figure 7.

Figure 9 is a horizontal section taken on the line 9-9 of Figure 7.

Figure 10 is a vertical transverse section taken on the line 1010 of Figure 4.

Figure 11 is a top view, drawn to a smaller scale, corresponding to Figure 7 but showing the parts in proper spaced relation to each other.

In the drawings A broadly designates a high voltage air break switch comprising a single phase. However, switches of this general type are usually employed for multiphase operation in which additional units identical with that shown in Figure 1 may be incorporated with links interconnecting the operating mechanisms to insure simultaneous operation of the switch blades. Switch A comprises a channel iron base 1 or any other rigid support. The base is shown horizontal but may be vertical. Secured to base 1 is a pair of spaced,

stationary insulators

2, 3 and an intermediate movable insulator 4 which includes a downwardly extending shaft 5 adapted for rotation in a bearing 6 mounted in base 1. For the purpose of operating switch A singly or as a part of a multi-phase switch, a crank arm 7 is fixed upon shaft 5 and projects radially therefrom. Crank arm 7 is provided with an operating eye 8 for connection to a rod (not shown) for interrelating the operation of a plurality of switches in a multi-phase switch.

Mounted upon the upper end of insulator 3 i a narrow, metallic conductor plate 9 supported at one end on movable insulator 4. Engaging conductor plate 9 is a connector 10 comprising opposing plates 11 clamped together by bolts 12 and having cooperating grooves for snug reception therein of a line conductor 13. In a multibladed single phase switch, insulator 3 could be eliminated and conductor plate 9 mounted upon adjacent insulators 4.

Bolted to the upper end of insulator 2 is a terminal support 14 having an upwardly extending portion 15, the forward face of which mounts a contact block 16 preferably of beryllium copper. From the central portion of block 16 (Figure 2) there project closely spaced, vertically aligned jaw-like contacts 17' and, intermediate thereof, a stop projection 18. Adjacent contacts 17, block 16 mounts a pair of stationary hook terminals 19, the outer ends of which are flared and are provided with shoulders 20. On the opposite end portion of block 16 there is a connector 21 of the same type as connector 10 for engaging a line conductor 22.

Rotatable with the upper end of insulator 4 is a support casting 23 (Figure 5), havin'g'at its upper portion an annularly shaped inner race 24 of an angular contact ball bearing 25, the outer race 26 of which mounts the lower portion of a cast cap or housing member 27, rotatable with respect to support casting 23. Cap member 27 has integrally formed in its upper portion aligned

tubular portions

28, 29 in axial normal relation to insulator 4 for extension therethrough of a tubular copper switch blade 30 which, by rotation of cap member 27, is swingable in a horizontal are about the pivot formed upon insulator 4.

Tubular portions

28, 29 mount angular contact type ball bearings 31, 32 journaling blade 30 for axial rotation.

A lever 33 depends from switch blade 30 and at its lower end mounts a ball 34 received between the arcuately faced arms of a clevis 35 integral with support casting 23 and projecting therefrom parallel to blade 30.

A clamp 36 on switch blade 30 mounts the ends of re silient, arcing horns 37 of copper, having coils 38 to increase their resiliency and spaced apart vertically, one above and one below blade 30. An upright arcuate yoke 39 has its upper and lower ends apertured to receive horns 37 and hold them spaced apart. The intermediate concave portion of yoke 39 is normally thrust against blade 39 by the resiliency of horns 37. Horns 37 are normally substantially parallel to blade 30 and terminate adjacent the end thereof and engage with book terminals 1h when switch A is closed.

Fixed on the end :of switch blade 3% is a contact element 411*, preferably of beryllium copper, having opposed upper and lower surfaces for conductive abutment against contact jaws 17. The distance between the upper and lower jaws 17 is less than the distance between the upper and lower surfaces of contact element 46. Through the spring quality of the beryllium copper, jaws 17 are suiticiently elastic to yield for receiving element 40 for switch closure. However, considerable force is necessary to effect such yielding so that relatively great unit pressure is developed upon the contacting areas of jaws 17 and element 40.

integral with support casting 23 and projecting upwardly therefrom adjacent its outer margin are lugs 41 (Figures 1, 7) for engagement with

sp'a'ced stops

42, 42 integral with cap casting 27. Preferably there is sutficient space between each

stop

42, 42 and-the adjacent ends of lugs 41 to provide lost motion between cap member 27 and support casting 23. Abutment of lugs 41 against either

stop

42, 42 will terminate their relative movement and cause cap member 27 and support 23 to rotate together upon continued movement of insulator 4 in the respective direction.

Conductor plate 9 is secured to a bolt b integral with and projecting from the top of cap member 27; and also secured by bolt [1 under conductor plate 9 is support 9 plate 43 for the generally semi-circular conductive member dd (Figure 4) extending partially about cap member 27 and including in one segment a pair of spaced

conductor posts

45, 46 connected bya current carrying arcuate section 47 terminating in open position blade stop 51. The other segmental portion of conductive structure 44 consists of vertically spaced concentric pairs of arcuate contact arms or

jaws

48, ,9; contact arms 49 being relatively short while contact arms 48 are extended at their ends to a point substantially diametrally opposite blade stop 51. Received between cont-

act arms

48, 49 for conduction is a cylindrical contact element 50, preferably of beryllium copper, securely mounted upon the adjacent end of switch blade30 which projects beyond tubular portion 23. Contact element 50 will be in contact with sets of

arms

48, 49 when switch blade 30-is in switch closed position (Figure 4). As may best be seen in Figure 5, bolt b atits lower end is provided with a smooth peripheral portion c received within a'ligned openings in conductor plate 9 andsupportplate43 forming friction bearr ings to permit movement ofcap 27relative to conductive structure 44 and plate9.

When switch A is in .closedposition (Figure 2), stop 13 will abut against the side of contact element 40 to limit movement of same into jaws 17. With contact element 49 thus received between jaws 17, cylindrical contact element 50 will engage contact

arms

48, 49, whereby current flow will be established throughout the length of switch blade 30 and the circuit between

conductors

22 and 13 fully closed.

Switch A is opened by rotation of arm 7 turning shaft and support casting 23' relative to cap member 27, as lugs 41 travel from stop 42' to stop 42. By such action clevis member 35 will be swung and cause a rocking of lever 33 as from the position shown in Figure 3 to that shown in Figure 8 to etfect-axia'l rotation of blade with contact element 4% being turned so as to remove its edge surfaces from engagement with jaws 17 (Figure 6), thus breaking the pressure joint therebetween. Rotation of cap member 27 under the counter rotation influence of clevis upon lever 33 and self :aligning ball 34 is resisted by the inherent friction between contact arms 4-3 so that blade 3b is rotated before such friction is overcome. The extent of axial rotation of switch blade 30 is limited by engagement of lug 41 and stop 42, and continued turning of shaft 5 after such engagement will accomplish joint rotation of cap 2'7 and support casting 23 to cause switch blade 30 to be swung in a horizontal plane about the axis of shaft 5 away from contact jaws 17 to full open position against stop 51. The distance between stop 51 and the blade pivot enables the stop to offer a firm resistance to the swinging of the blade, whether resulting from the momentum of the initial pull by the operator or by a continued pull by the operator.

Resilient arcing horns 37 will remain in circuit-carrying relation with hook terminals 19 during initial movement of switch blade 30 outwardly. When blade 30 has been swung outwardly a predetermined distance from contact jaws 17, arcing horns 37 (as indicated in broken lines in Figures 7 and ll) will be pulled from engagement with terminals 19 and thereupon instantaneously spring towards blade 3t) until yoke 39 engages the blade. Such engagement will prevent horns 37 from swinging the greater distance which otherwise would be. induced by their resiliency and then oscillating back again into a position where the arc would be restruck. The distance traveled by blade 30 prior to separation of arcing horns 37 will be sufficient to prevent the re-striking .of an are between same and contact jaws 17 or terminals 19. Thus, arcing horns 37 are of such length and resiliency as to assure the arrival of switch blade 30 at a safe distance prior to .the complete interruption .of current flow. Duplicating arcing horns 37 reduces the current value of each rod and accordingly reduces the arc voltage when the switch is completely opened by the release of horns 37 from terminals 19..

When blade 3.0 is swung in the opposite direction to close the switch, the thrust of yoke39 on l1orns.37 is so close to the outer ends of these rods that they are posi tively moved into engagement with terminals 19 instead of flexing between their ends and the rod anchorage 36 and to avoid passage to the horn shoulders 20.

The opening movement of .blade 30 is limited byabutment of same against stop 51 of conductive structure 44 (Figure 7).

During the opening movement of blade 30, contactelement 50 will travel along contact arms 48 and be held by the ends thereof at termination of the swinging of the blade. Thus, throughout the switch-opening operation, switch blade 30is maintained in conductive relation with portion 13 of the transmission line through the cooperation of contact element 50 and contact arms 48. This unique feature prevents destructive arcing as would occur if only the blade is involved in .switch opening operation.

To close the switch, crank arm 7 .is swung. in the opposite direction to move blade 30 toward contact jaws 17. On the initial swinging of crank arm 7 in this direction, support casting 23 will move relative to cap 27 until upon engagement of blocks 41 with stops 42, the lost motion between support member 23 and cap member 27 terminates, rotating blade 30, and restores contact element 40 to full upright position for switch closure so that the same will move together through the remaining are of travel of crank arm 7. Sufficient inertia is applied to arm 7 so that contact element 4.0 is forcibly driven between jaws 17 which, under the. impact of such inertia, will yield sufiiciently for reception .of element 40. During closure arcing horns .37 are forcibly engaged with terminals 19 by movement of blade 30 toward contact jaws 17 upon yoke 39. Yoke 39 exerts positive thrust upon horns37 substantially free of elasticity from coil 38.

As shown above, contact element 40 is adapted for what might be termed locked or unlocked position. When in so-called locked or conductive position, the angularity between the jaws 17 creates pressure between same and element 40 sufiiciently great to prevent their accidental disengagement. Contact element 40 must be rotated to unlocked position through axial rotation of blade 30 for'disengaging'the contactfromjaws 17. The

an)" I movement of element over contact jaws 17 effects a cleansing or wiping action on the jaws so that any moisture, oxides, dirt or the like which may have accumulated thereon will be removed, whereby effective conductivity will be maintained. The provision of a pair of resilient arcing horns 37 sustains current flow until blade 30 has been removed from jaws 17 far enough to prevent restriking of arc. Blade 30 extends completely through cap structure 27 and thus swings about a pivot or center between its ends. Both ends of blade 30 carry contact elements, one of which is continuously maintained in current carrying contact with the cooperating stationary elements to prevent damaging arcing.

The details of construction may be varied without departing from the spirit of the invention and the exclusive use of those modifications coming within the scope of the claims is contemplated.

What is claimed is:

1. A high voltage switch comprising a base, at least one fixed insulator mounted on said base, vertically spaced contact jaws mounted on said fixed insulator, a shaft suitably journaled in said base, a support member rigidly secured on said shaft for movement therewith, a cap member mounted on said support member for relative horizontal rotative movement with respect thereto, a pair of stationary, vertically spaced, arcuate contact arms in a concentric relation to said cap member, a switch blade journaled in said cap member in axial normal relation to said shaft for switch opening and closing swinging movement responsive to operation of said shaft, said switch blade extending at each of its ends beyond said cap member, and a contact element carried on each projecting end of said blade, one of said contact elements being presented for circuit closing relation with contact jaws, the other contact element being in continuous conductive engagement with said contact arms which describe an arc of at least equal extent to that through which the blade swings.

2. A high voltage switch comprising vertically spaced contacts, a switch blade mounted for axial rotative movei ment within a horizontal plane, a contact element on one end of said blade for reception between said contacts, means for rotating said blade axially for circuit-closing pressure-developing engagement of said contact element with said contacts and for breaking such engagement for switch opening, vertically spaced stationary arcing terminals adjacent said contacts, and a pair of resilient arcing horns carried by said blade for current sustaining engagement with said arcing terminals, said resilient arcing horns being adapted to retain engagement with said arcing terminals after breaking of engagement between said contacts and contact elements.

3. A high voltage switch comprising a base, a shaft journaled in said base, a support member rigid on said shaft, a generally conically shaped cap member rotatably mounted on said support member, a switch blade journaled for axial rotation in said cap member and in axially normal relation to said shaft, said cap member having an opening the sides of which define stop surfaces, an upstanding lug provided on said support member for engagement with said stop surfaces whereby said members will rotate jointly on operation of said shaft for opening and closing swinging of said switch blade, and means for effecting axial rotation of said blade prior to engagement of said interengageable members.

4. A high voltage switch comprising a base, a shaft journaled in said base, a support member fixed on said shaft, a cap member rotatably mounted by reduced friction bearings on said support member, a fixed conductor supported on said base, said cap member being mounted on said fixed conductor through a friction bearing for swinging movement with respect to same, a switch blade journaled by reduced-friction bearings in said cap member for axial rotation, interengageable members provided on said cap and support members and limiting axial 6 rotation of said blade, and cooperating members pro vided on said shaft and said blade, whereby upon operation of said shaft the friction differential of said friction bearing and reduced-friction bearings will effect axial rotation of said blade prior to swinging of said cap member by engagement of said interengageable members.

5. In a high voltage switch, a pivot terminal, vertically spaced jaw terminals spaced therefrom, vertically spaced arcing terminals adjacent said jaw terminals, a blade of circular cross section pivoted near one end to said pivot terminal for swinging movement within a horizontal plane with its other end movable into and out of contact with said jaw terminals, a pair of resilient arcing horns extending lengthwise of said blade on diametrally opposite sides thereof and anchored thereto adjacent to said pivot terminal to be moved by said blade into and out of contact with said arcing terminals, said horns being distortable upon movement of the blade away from said jaw terminals until the blade has moved therefrom beyond the length of the maximum arc of the current voltage for which the switch is adapted, structure limiting movement of said horns in one direction past said blade while leaving the horns free of said blade, outwardly of their anchorage thereto, to move under distortion away from said blade in the opposite direction.

6. In a high voltage switch, a pivot terminal, vertically spaced jaw terminals spaced therefrom, vertically spaced arcing terminals adjacent said jaw terminals, a blade of circular cross section pivoted near one end to said pivot terminal for swinging movement within a horizontal plane with its other end movable into and out of contact with said jaw terminals, a pair of resilient arcing horns extending lengthwise of said blade on diametrally opposite sides thereof and anchored thereto adjacent to said pivot terminal to be moved by said blade into and out of contact with said arcing terminals, said horns being distortable upon movement of the blade away from said jaw terminals until the blade has moved therefrom beyond the length of the maximum arc of the current voltage for which the switch is adapted, a yoke connecting said horns at points spaced from the horn anchorage and movable with said horns relative to the blade and having a blade-engageable face at the jaw terminal side of the blade to limit recoil movement of said horns.

7. A high voltage switch comprising a base, a shaft journaled in said base, a support member rigid on said shaft, a cap member rotatably mounted on said support member, a switch blade journaled for axial rotation in said cap member and in axially normal relation to said shaft, a clevis fixed on said shaft in axially parallel relation to said blade, a lever fixed on said blade projecting axially normally therefrom for engagement With said clevis whereby, upon operation of said shaft, swinging of the clevis will effect axial rotation of the shaft.

8. A high voltage switch comprising a base, a shaft journaled in said base, a support member rigid on said shaft, a cap member rotatably mounted on said support member, a switch blade journaled for axial rotation in said cap member and in axially normal relation to said shaft, a clevis fixed on said shaft beneath, and axially parallel to, said blade, a lever fixed on said blade for downward extension therefrom for engagement with said clevis, whereby, upon operation of said shaft, swinging of the clevis will effect axial rotation of the shaft.

9. A high voltage switch comprising a base, a shaft journaled in said base, a support member rigid on said shaft, a cap member rotatably mounted] on said support member, a switch blade journaled for axial rotation in said cap member and in axially normal relation to said shaft, a clevis fixed on said shaft beneath, and axially parallel to, said blade, a lever fixed on said blade for downward extension therefrom, a spherical member mounted on the lower end of the lever for engagement with the clevis, whereby, upon operation of said shaft,

swinging of the tclevis will effect axial rotation. of the shaft. 7

.10. A high voltage switch as described in claim 9 wherein :the inner .facestof the clevis, are ancuatedfor abutting engagement with the spherical member.

11. A high. voltage switch comprising-a :pair :of contact jaws, an elongated blade mounted to :swing about a pivot transversely of its length into and out of engagement with said jaws, said blade beinga'otatable about its longitudinal axis, a stationary arcing member adjacent said contact jaws and having terminals :at opposite sides of and spaced from said :switch blade, a .pair of elongated resilient arcing horns carried on opposite sides of said blade and normally substantially parallel thereto and rotatable therewith about the blade axis, said horns being disposed to engage said :aitc-ingmember. terminals when the switch is Closed, eachof said arcing member tenninals having a horn contacting surface elongated :inthe dineetion of movement .of the-arcing horns: when the latter are rotated about the said blade axis, said arcing horns being of such length as to retain engagement with said arcing terminals when saidlzblade .iskswung on its pivot away :from :said content jaws nntilsaid blade has been moved a predetermined distance from said contact jaws.

References'Cited in the file of this patent UNITED STATES PATENTS 1,695,868 Stolz Dec.18, 1928 2,231,992 Ejellstedt Feb. 18, 1941 2,317,118 Schultz et a1. Apr. 20, 1943 2,521,484 Schmidt r v Sept. 5, 1950 2,531,165 Seheuermeyer Nov. 21 1950 2,551,271 Kuwayama May ,1, 1951 2,610,276 Bayer Sept. 9, 1952 2,688,666 Gilliland et al. Sept. 7,, 1954 2,727,105 Turner "Dec. 13, 1955