US2955181A

US2955181A - High voltage switch mechanism

Info

Publication number: US2955181A
Application number: US761977A
Authority: US
Inventors: Elmer L Luehring
Original assignee: Hi Voltage Equipment Co
Current assignee: Hi Voltage Equipment Co
Priority date: 1958-09-19
Filing date: 1958-09-19
Publication date: 1960-10-04
Anticipated expiration: 1977-10-04

Description

O 1960 E. L. LUEHRING 2,955,181

' HIGH VOLTAGE SWITCH mscmmsm Filed Sept. 19, 1958 5 Sheets-Sheet 1 2; FIG.

INVENTOR.

ELMER l LUEHRING ATTORNEY Oct. 4, 1960 E. L. LUEHRING 2,955,181

I HIGH VOLTAGE SWITCH MECHANISM Filed Sept. 19, 1958 5 Sheets-Sheet 2 INVENTOR. ELMER L. LUEHR/NG BWM'W WWW ATTORNEY 5 Sheets-Sheet 3' m GI Oct. 4, 1960 E. L. LUEHRING HIGH VOLTAGE swrwca uscmmrsu Filed Sept. 19, 1958 Oct. 4, 1960 E. L. LUEHRING 2,955,181

HIGH VOLTAGE SWITCH MECHANISM Filed Sept. 19 1958 5 Sheets-Sheet 4 ECN T'ESS 7/ AS (ACTUATOR 4 a STOP 3L6!) A(ARC HORNS 27,26) 522,19 NHMAIN SWITCH |s,|5) (4,23

SEQUENCE NO (18MB) (2762s) (22%|) (345340) (36%) FULL CLOSED l CLOSED OPEN OPEN CLOSED CLOSED OPENNING 2 CLOSES 3 OPENS 4 CLOSES OPENS 5 OPENS II 6 OPENS II 7 OPENS n 8 CLOSES I. 9 CLOSES FULL OPEN IO OPEN OPEN OPEN CLOSED CLOSED CLOSING "H CLOSES II I2 CLOSES 3 OPENS H I4 CLOSES u 5 OPENS FULL CLOSED l CLOSED OPEN OPEN CLOSED CLOSED 4 INVENTOR.

ELMER L. LUEHR/NG Ma/MW Wm ATTORNEY Oct. 4, 1960 E. 1.. LUEHRING HIGH vormcs swITcH MECHANISM 5 Sheats -Sheet 5 Filed Sept. 19. 1958 O N EB 3, H s E B 0 P 00 L 0 L 6 0 CC 23456 89 l HQBM5 D EE N S mmm 1w ECNHHHHHHHOS U N LO QLE L ELP UC U SUO F F C...

'3 2 4/ b m m w m VIAS & RM HV m 3 l m VVL R 6 k 8 7 v FIG. 5

INVENTOR. ELMER l LUEHR/NG gLzm/W mm ATTORNEY atent Ofiice 2,955,181 Patented Got. 4, 1960 HIGH VOLTAGE SWITCH MECHANISM Elmer L. Luehring, Cleveland, Ohio, assignor to Hi- Voltage Equipment Company, Cleveland, Ohio, a division of Joslyn Mfg. and Supply Company, a corporation of Illinois Filed Sept. 19, 1958, Ser. No. 761,977

'6 Claims. (Cl. 200-146) This invention relates to high voltage switches and has particular significance in connection with vacuum interrupter actuation for such switches. A single pole unit is shown but ordinarily a plurality of switches are interconnected for three pole (i.e., three phase) operation.

High voltage switches have been extensively employed in the past, particularly in connection with outdoor switching stations for isolating sections of transmission lines and associate apparatus. Such high voltage switches are generally air-break switches provided with arcing horns as for interrupting transformer magnetizing currents, and in recent years there have also been associate vacuum bottle interrupters to prevent arcing even at the arcing horns.

One difi'iculty in the past has centered around the necessity of coordinating the operation of main switches, arcing horns and vacuum bottles. Any equipment used must be rugged, reliable, positive acting, and operable with little power such as may be easily exercised by one man through remote lever operating mechanism.

An object of the present invention to provide simple and inexpensive means for overcoming the above mentioned difliculty.

A further object is the provision of mechanism in which requirements for replacement or repair or modification are reduced to a minimum.

Another object of the invention is to provide improvements in toggle operating actuators as for vacuum bottle interrupters.

Another object is to provide mechanism having sinusoidal change of velocity of force application for toggle operation both on opening and closing of associate switch vacuum bottle apparatus.

Other objects and advantages will become apparent and the invention will be better understood from consideration of the following description taken in connection with the accompanying drawings in which:

Fig. 1 is a side elevation showing one pole of a high voltage switch with the switch arm in closed position;

Fig. 2 is an enlarged side view portion of the main switch shown part open and showing a vacuum interrupter portion with the vacuum interrupter contacts in closed position;

Fig. 3 is an opposite side perspective view of the top actuator mechanism for the modular vacuum bottles of Fig. 2 and shown with the mechanism cover removed and with the actuator in an intermediate position;

Fig. 4 is a one line simplified electrical circuit diagram with an accompanying table to show typical operational sequence for the apparatus of Figs. 1-3; and Fig. 5 is a perspective and tabular portion illustrating a modification.

Referring to the general arrangements of Fig. 1, a base member is shown carrying a switch mechanism including fixed

insulators

11 and 12 and a rotatable insulator 13. The insulator 12 carries a contact support plate 14 in turn carrying a fixed main switch contact 15 having a contact cover 16 and there-beneath a slot into which a main switch blade 18 (see Fig. 2) of a switch arm 19 is moved when the switch arm is in closed position.

Insulator 11 through a bracket 21 thereon provides a stationary swivel support for the switch arm 19 and its operating mechanism with suitable terminal members 22-23 being provided to take current to and from the parts of the main switch.

Crank arms 24-24 are conventionally connected to a motor or hand operating lever and the arrangement is such that as the insulator 13 is thereby rotated the main switch arm 1% (on closing) will first swing downward in an arc and thereafter the blade 18 will slide horizontally inwards into its contact slot, and on reverse action (for opening) the arm is first moved horizontally to disengage the blade from the slot after which the arm is swung to a vertical position (see US. Patents 1,829,349; 1,962,305; and 2,514,263).

Mounted with respect to the contact support plate 14 is a torsion rod biased arcing horn 26 cooperating with an arcing horn 27 which also serves as an actuator driver sleeve as hereafter more fully explained.

in recent years line charging currents, transformer charging currents and capacitor interrupting currents have been so large that air break switches even when provided with arcing horns are not entirely satisfactory without also employing one or more vacuum interrupter breaks or bottles in a sequence controlled circuit. Thus, as shown in Fig. 1, three vacuum interrupter assemblies 30 may be employed operable from movement of an actuator arm 32 as it is forced to the left in Fig. 1 (to open the bottles during one portion of the sequence of main switch opening) or as it falls back down by gravity (to close the bottle contacts during another portion of the main switch opening sequence as hereafter described).

As explained and illustrated in copending patent application, Serial No. 711,196, filed January 27, 1958, by E. L. Luehring, and H. E. Poe, and assigned to the assignee of the present invention, each bottle assembly 30 may have an outer shell 32 (see Fig. 2) of insulating material with flange holes provided for receiving bolts 33 for fastening together like units, and each containing a glass 34 enclosed vacuum interrupter comprising coaxial contact rods 34a extending into the glass envelope, one from each of two end caps, and engaging the other rod within the envelope. Usually a bellows 34b is interposed between the movable one of the rods and the envelope for preserving the vacuum. A cellular foam 35 is used around and above and below the envelope of each interrupter 34, and vertical insulating material tubes 36 each contain an insulating material operating rod 37 operating a cross-bar 38 for each unit.

At their upper ends rods 37 are secured with an operating plate 39, which in turn is operated vertically by an eye bolt 49 secured by means of a pin 41 with respect to a lower toggle link 42 which cooperates with an upper toggle link 43 to form a toggle. A pin 44 fastens the two links together and a pin 45 secures the upper end of link 43 with respect to a stationary toggle frame 46 mounted on a base 47 supported as shown on an adapter plate 48 fastened to the assembly of modular bottles.

In accordance with the present invention a point of application to the toggle is at a point other than an end or center. As shown a pin 58 is used to secure the ends of a pair of coil springs 51 at a point adjacent but disposed away from pin 41 slightly toward the center of the toggle. The far ends of the springs '51 are held by a spring and actuator crank 53 operated by a shaft 54 (see Fig. 3) journaled in a crankshaft bearing 55, fixedly supported with respect to the base 47. The far end of the crankshaft 54 terminates in a flange 56. The actuator arm 31 terminates in a corresponding flange 57 and it has been found advantageous to secure these flanges together by nut secured bolts 58 extending through arcuate clearance slots to provide some adjustment of the one flange with respect to the other. Other desirable adjustments are provided by a nut secured cap screw 59s, the adjustment of which (into a relatively straight toggle) determines the sensitivity, and a nut secured cap screw 59d, the adjustment of which (into the collapsed toggle) will change the stroke of the eye bolt 40. Meanwhile the relative position of the two hubs 5657 may be used to adjust trip-off without opening an actuator cover 66 desirably provided to protect the toggle actuator mechanism from the elements (see Figs. 1 and 2). This outside adjustment can be used to determine sequence of switching which may, for many installations, be other than that hereafter described by way of illustration.

A torsion bar mounted actuator arm stop 61 is provided to limit downward travel of actuator arm 31 and in operation these parts (31 and 61) also serve to short out the circuit of the vacuum bottles for certain steps of the sequence of operation as schematically and in tabular form explained by Fig. 4 which also shows that a series connection to the bottles is made only when the arcing horn and actuator driver 27 is in contact with the actuator arm 31.

For the purpose of preventing currents through the bearing 55 (Fig. 3) an upper flexible cable shunt 63 extends as from a point of attachment on the actuator crank 53 to a bolt connecting with a strap shunt 64 which in turn may connect (as shown in Fig. 2) with a top terminal 65 on the assembly of modular bottles 30 each having a top lead 66, a bottom lead 67 and a bottom terminal 68.

The mechanism just described operates as follows:

Assuming that the main switch is closed (as shown in Fig. 1) switch opening action is initiated by rotation of crank arms 24 turning insulator 13 in such a direction that switch arm 19 is horizontally withdrawn to disengage its blade 18 from main contact 15, but this movement (leftward in Fig. 1) first closes arc horn 27 upon 26 so that as the main contacts open the circuit is shifted from the main contacts to the auxiliary arcing horns 2627 (because even though the bottles are closed there is not yet established an electrical circuit to them).

With continued rotation of insulator 13 the arm 19 and its blade 18 swing upward in an are causing the arc horn driving sleeve 27 to engage the actuator arm 31 and an electrical circuit may be traced from terminal 22 to'arm 19, blade 18, sleeve 27, arm 31, flange 57, flange 56 (Fig. 3), shaft 54, crank 53, upper cable shunt 63, strap shunt 64, terminal 65, modular top lead 66, top interrupter 34, first modular bottom lead 67, terminal 63, and so on down through as many more modular units as there may be and finally through a shunt 69 connecting with the metal main contact support 14 and thus to terminal 23.

With continued upward arcuate movement of main blade 18 (see Fig. 2) the arc horns (27, 26) open.

With additional upward movement of the movable horn and driving sleeve 27 the actuator arm 31 is carried upward thus turning the spring and actuator crank 53 until the latter, e.g. through an operating protrusion 70 with which it may be equipped, eventually knocks the upper toggle link 43 (or the toggle center, or any portion of either toggle link except its far end) out of vertical alignment. During all of arm 31 upward travel crank 53 is, because its center of rotation is properly eccentric with respect to pin 50, sinusoidally building up tension in the springs 51 so that as soon as the toggle is placed oif vertical center,

parts

40, 39, 37 and 33 quickly spring up and the circuit is broken through the various vacuum interiupters of the modular assembly.

As a next step the driving sleeve 27 leaves the end of actuator arm 31, and then arm 31 falls back down due to its own weight, crank 53 returns and the springs, which are designed to have some force at this point, and which are attached to the bottom toggle link above the center of rotation of the latter, pull the toggles back to vertical alignment which closes the bottles and relaxes the springs. As the actuator arm drops down it not only thus recloses the bottles, but by its ultimate contact with the stop-arm 61 mounted as by a torsion bar metallic portion with respect to the main contact support 14 it shorts out the bottles. Thus, the bottles are closed, and shorted out for the major portion of switch operation (that is, during main switch full open, during main switch full closed, and during all main switch closing).

During main switch closing (from an assumed full open vertical position of switch arm 19) the arc horn driving sleeve 27 first contacts stationary arc horn 26, and then as it continues its downward arcuate movement it will force actuating arm 31 (held only by the torsionally resilient stop 61) out of the way and then after its final horizontal movement when the blade 18 is pushed full into the main contact 15, it assumes the position shown in Fig. 1, and thus the electrical circuit is transferred from the arc horns to the main switch contacts.

Even though the bottles are closed all the time the main switch closes, there is no circuit through them until after the arcing horns close, and even then the bottle circuit is shunted, but this can be modified more easily than with prior art arrangements to permit, where desired, having the bottles stay open until the main switch contacts are fully closed. That is to say that though in some capacitor installations tremendous inrush currents have heretofore required that the load be picked up by the main contacts before bottle contacts close, this is no longer necessary according to arrangements as disclosed above and whereby the bottle contacts can be kept unaffected by the main circuit whether open or closed, and still equipment according to the invention is easily susceptible of modification to keep bottle contacts open during main switch closing whenever desired. As an example and as illustrated in Fig. 5 the'insulating material operating rods 37 in tubes 36 may be carried right on out in the form of extensions 37:; passing through the bottom of the lower modular unit 30 and equipped with wear resisting metal end tips 37m. The main contact base 14 is divided into a stationary top portion 141 having holes for accommodating the rods or tips, an intermediate shuffle plate 72 having holes 73 for accommodating the rods for one position of the plate 72, terminal 23 having holes for accommodating the rods, and a bottom portion 1412 having holes for accommodating the rods for one position of shuffle plate during one position (the closed position) of actuator mechanism and bottle contacts. The shuflie plate 72 moves in guide ways 74 and is arranged to be biased in one direction as by a spring means indicated diagrammatically at 75 except during main switch closing when it is biased in the opposite direction by an arm 76 urged to the right (in Fig. 5) by driving sleeve 27 during entrance of the main switch blade 18 into the fixed main switch contact 15. During operation the electrical and mechanical action of other parts will be as before (see table, Fig. 4-) except for the bottle contacts which will operate as indicated by the tabular portion in Fig. 5 where it will be seen that for main switch opening the situation is the same as in the prior case (Fig. 4) until step No. 6. Then, as the bottle contacts open the extensions 37:: are withdrawn from the holes 73, and shuffle plate 72 snaps to the left (as viewed in Fig. 5). Later, at step 8 when the actuator arm falls by gravity, the tips 37m engage solid portions of plate 72 and the bottles can not reclose until, for example, the final closing step 15 when the main switch blade will have advanced far enough into the fixed contact receptacle 15 to return arm 76 and attached plate 72 so that the holes and rods are again in correspondence and the bottles may close due to the reset (toggle straightening) action of the springs 51.

There is thus provided a device of the character described which is relatively simple and capable of meeting the objects above set forth.

The toggle actuator mechanism of the invention is ad vantageous in permitting ease of adjustment, either through the cap screws or the slot bolts, or by replacement of the coil springs with springs of different dimensions as during assembly to take care of a difierent number of tandem connected bottles.

The point of application of force to the toggle other than at an end or center thereof permits collapse and reset of the toggle from the same spring means and the particular toggle mechanism disclosed has the advantage of allowing gradual spring buildup combining with sudden application of the spring force for opening the bottles, so that the movable arcing contacts can move at very high speed especially because of the lightness of the associated parts plus the large amount of energy stored in the spring means. Thus, an arc can be drawn in a very short time and the circuit interrupted in a cycle or less. Further, it should be noted that the exact energy of the spring has little to do with operating the toggle (except for reset) and this is one thing which permits changing size of spring to accommodate different numbers of bottles. The arrangement is further advantageous in that after the springs have pulled the toggle back to vertical alignment, and thus for the great majority of the time, the springs are relaxed, and with the arrangement of the invention all of the main operating parts (37, 38, 39, 40) all have a straight line motion easily imposed on them as by a pair of small rollers 78 mounted on pin 41 and engaging a flat track 79 on a bracket 80 also serving to mount adjusting screw 59s. The springs are wound up (extended) during complete travel of the actuator arm as opposed to prior art toggle arrangements where much motion is wasted before extending a spring all at once or where a spring winds up only during half of travel and then trips and the second half of actuator travel is wasted.

While particular embodiments have been illustrated and described, various modifications may obviously be made without departing from the true spirit and scope of the invention intended to be defined by the appended claims.

I claim:

1. A high voltage switch having first, second, third and fourth switch means with the first switch means comprising a fixed main contact and a movable main contact, the second switch means comprising co-operating stationary and movable arcing horns electrically arranged directly in parallel with the main contacts and mechanically arranged to open after the main contacts open on opening, the third switch means comprising at least one vacuum interrupter having contacts and a conductive operating arm in circuit with and for moving one of the contacts of said interrupter with respect to the other which is fixed and with the interrupter contacts electrically arranged in a circuit which parallels the circuit of the arcing horns and thus parallels the circuit of the main contacts and with the mechanical arrangement such that the interrupter contacts will open after the arcing horns on opening, the fourth switch means comprising the movable arcing horn and said operating arm electrically in series with the contacts of the third switch means and therewith forming a part of the parallel circuit around the first and second switch means with the parts mechanically configured and arranged such that the switch formed by said horn and arm will open after the first switch means, after the second switch means and after the third switch means on opening.

2. A high voltage switch as in claim 1 further characterized by fifth switch means comprising the conductive operating arm in co-operation with a mechanical stop electrically connected with respect to the fixed main contact, whereby except for sequence of opening and closing the fifth switch means is directly in parallel with the third switch means and the parts may be readily configured and arranged so that upon full closure of main contacts the vacuum interrupter will always be shorted out by said fifth switch means.

3. In a switch having a stationary main contact and a movable main blade co-operating therewith in combined arcuate and rectilinear movement, a relatively fixed arcing horn electrically and mechanically associated with the stationary main contact, a movable arcing horn electrically and mechanically associated with the blade, and at least one vacuum switch, the combination of an actuator arm secured at one end thereof for rotation when its other end is moved upward by contact with the movable arcing horn moving upward, a stop for limiting the travel of the actuator arm when it returns by gravity after disengagement with the movable arcing horn, a crank having a center of rotation and arranged to be rotated in one direction or the other by rotation of the actuator arm, a spring biased toggle comprising two links a point on one of which is other than at the end thereof and other than at the center of the toggle and is spring connected to a point on the crank, said points being eccentric with respect to the center of rotation of the crank and with respect to each other to permit a sinusoidal build-up of forces on the toggle with travel of the actuator arm in such manner that the toggle links are substantially aligned at one limit of travel of the actuator arm and collapsed at the other limit of travel thereof, and a connection from one end of the toggle to operate the vacuum switch.

4. In a switch according to claim 3, the combination further characterized by adjusting screw means for setting the relative rotatable position of the actuator arm with respect to the relative rotatable position of the crank, adjusting screw means for setting the amount of collapse of the toggle when collapsed, and adjusting screw means for setting the point of straightening of the toggle when relatively straight.

5. In a high voltage switch, the combination of main switch blades, arcing horns connected directly in parallel with the main blades, a vacuum switch connected substantially in parallel with the main blades and arcing horns, means including mechanical configuration and inter-attachment for opening the arcing horns sequentially after opening of main blades and for closing the arcing horns sequentially before closing of main blades, means including mechanical configuration and mechanical interattachment for opening the vacuum switch sequentially after opening of arcing horns, means including a spring for reclosing the vacuum switch, and means for rendering said spring inoperative to close the vacuum switch until the main blades close.

6. In a high voltage switch mechanism comprising main switch blades, are horns electrically associated with the main switch blades and closeable on each other, and at least one vacuum interrupter, the combination of electrical connections for the interrupter including a lever actuator for the interrupter said lever actuator being mechanically and electrically contactable by one of the arc horns acting as a driver, a stop for the lever actuator mechanically and electrically contactable thereby and electrically connected with one of the main blades, with the circuit of the interrupter placed in parallel with the circuit of actuator and stop and with this parallel circuit in series with the circuit of driver and actuator and with this series and part parallel circuit in parallel with the circuit of the arc horns and with the circuit of the main blades to permit a sequence on opening of arc horns close, main switch next opens, driver and actuator next close while actuator and stop open, arc horns next open, interrupter next opens, driver and actuator next open, interrupter closes, and actuator and stop next close to short out interrupter, while on closing arc horns first close, main contacts later close, and then arc horns open while the interrupter remains shorted out by actuator and stop all during closing.

References Cited in the file of this patent UNITED STATES PATENTS 2,838,638 Date June 10, 1958