US2765380A - High current disconnecting switch - Google Patents

Description

Oct. 2, 1956 H. w. GRAYBILL HIGH CURRENT DISCONNEZCTING SWITCH 4 Sheets-Sheet 1 Filed Nov. 4, 1952 Oct. 2, 1956 H. w. GRAYBILL 2,765,380

HIGH CURRENT DISCONNECTING SWITCH Filed NOV. 4, 1952 4 SheetsSheet 2 Oct. 2, 1956 H. w. GRAYBILL yuan CURRENT DISCONNECTING SWITCH Sheets-Sheet 3 Filed NOV. 4, 1952 WWW Oct. 2, 1956 H. w. GRAYB!LL 2,765,380

HIGH CURRENT DISCONNECTING SWITCH Filed Nov. 4, 1952 4 Sheets-Sheet 4 IN V EN TOR. 14,9114 w J/a OM M United HIGH CURRENT DISCONN'ECTING SWITCH Application November 4, 1952, Serial No. 318,638

11 Claims. (Cl. '200162) My invention relates to knife type disconnect switches in the high current class of the type which may be operated with a hook stick or gang operated from a remote position or other hydraulic, pneumatic or electrical means.

More particularly, my invention relates to a novel knife type disconnecting switch having a plurality of movable contacts and a plurality of stationary contacts.

In electrical switches of the type to which my invention relates, it is desirable to have a plurality of high pressure spot or line contacts in preference to surface or area contacts. That is, high pressure spot or line contacts permit metal to metal contact through dust, oxide, sulphide, film and ice.

Since the current ca rying capacity of a single spot contact is limited, it is necessary to have a dozen or more such contacts in order to carry a normal load current of several thousand amperes or higher.

Ho. 'ever, even though the prior art disconnect switches provided a plura ity of spot contacts in order to obtain-a high pressure contact and sufiicient cross-sectional area to carry large load currents, it was not possible to secure uniform contact pressure on the dozen or more contacting spots.

In the prior art arrangements, the jaws of the knife type disconnect switch were slotted and thereby provided a plurality of stationary contacts. That is, the semi-rigid jaw members were slotted and backed up by resilient means to urge them against the contact button of the switch blade. Although the switch blade was provided with a plurality of contact buttons to engage the individual slotted sections of the jaw members, the jaw member was a slotted unit and did not provide for flexibility of adjustment of the individual spot contact points.

Hence, when the slotted blade member closed over between the jaw tongue and the plurality of contacts on the slotted jaw members, it was impossible to have metal to metal contact between the blades and the center tongue in more than one or at the most two spots at each side of the center tongue.

Furthermore, the resilient members or clips urging the slotted portions of the jaws members toward the switch blade were not uniform in shape or physical characteristics and hence, could not exert uniform contact pressure.

In high current disconnect switches, it is of the utmost importance that the contact pressure be determined, properly adjusted and carefully controlled to remain constant. Since the resistance of the contact points will vary inversely as the pressure, provided all other factors remain constant, considerable variation in the voltage drop and heating will result when the pressure is non-uniform and varies over a considerable extent. That is, the current capacity of the disconnect switch and its associated contacts will vary with .the contact pressure and thus it is necessary to obtain a predetermined contact pressure for the switch. 7

On the other hand, there is a maximum orupper limit of contact pressure beyond which the material of the'contacting surfaces will gall under repeated operation.

atent O disconnect the aluminum pot lines from a rectifier.

ice

Hence, in view of the undesirable effects resulting from contact pressures which are either too high or too low, it is necessary to design a switch so that it will have a constant optimum contact pressure which is just below the critical pressure.

in the novel disconnect switch of my invention, 1 provide a structural arrangement wherein the contact pressure can be maintained at a predetermined magnitude and in'wh'ich each of the plurality of cooperating contacts flex independently and individually so as to insure contact at all of the plurality of the contact points.

lnorder to achieve these results, the switch of my invention is provided with blade members which are slotted between the contact spots thereby forming a plurality of fingers which canifiex'individually and independently.

Furthermore, the jaw members are provided with a plurality of resilient spring contacts which in turn are able to flexindividually and independently.

Aspring contact is provided for each blade finger so :that the engagement for the raised contact spots on the blade fingers and spring contacts will permit the latter to press the blade fingers with a predetermined pressure against the plane surface of the relatively heavy center jaw tongue. Thus, each of the plurality of cooperating contacts act independently and individually to insure proper contact pressure between the blade fingers and the center jaw tongue.

In this type of switch, the cente jaw' tongue carries "a large'rnagnitude of the'load current. However, the spring contactsare'al'so designed to carry a small portion of this current and are made from ahigh-strength, high-conductivity, precipitation-hardened alloy such as beryllium copper. Spring contacts of this material are not subjectto annealing at temperatures normally encountered in this type of disconnect switch.

Accordingly, with the switch of my invention in which a plurality of cooperating contacts are formed between flexible fingers and spring contacts, alignment of the contacting surfaces is achievedby merely closing the switch blade over the center jaw tongue before the hold down bolts are tightened and no further'adjustment is required.

A further feature of my invention is to provide sequential blade movement in which the outer pair of blades of the switch unit opens ahead of the inner pair of blades. Theseblade movements which may be used on either the hook stick operated or the gang operated switches, cuts in half the forcing effort required for opening the switch.

Contact pressure at the hinge endof the disconnect switch is supplied by heavy 'bellville spring washers. An auxiliary contact may be supplied on each blade in order to take the slight arc that may ocur when the current is transferred from the switch to a parallel circuit breaker.

It will also be noted'that the disconnect switches of my invention may be built in multiple units so that ten 6,000 ampere switchesinay be connected in parallel to result in a combined 60,000 ampere switch unit. Thus, the switch can be applied to disconnect cell lines from a rectifier or generator or wherever high cnrrent'switching is necessary at relatively low'voltages from 250 to 600 volts.

In one application of my novel disconnecting switches, they are connected in multiple units, as abovenoted, to The plurality of disconnect switches are connected in parallel witha 6,000 ampere circuit breaker which remains closed as the switch is opened. I When the switch is fully opened, an auxiliary switch in the motor mechanism trips the circuit breaker, which instantly interrupts the circuit.

Accordingly, it is a primaryobject'of my invention to provide a disconnect switch in which the contact pressure on the plurality of cooperatingcontacts can'bereadily 3 and carefully controlled and in which the pressure is fairly uniform on all the contacts.

It is another object of my invention to provide a contact arrangement in which the pressure will remain substantially constant for the life of the switch.

It is a still further object of my invention to provide a novel structural arrangement wherein a plurality of co operating contacts for a knife type disconnecting switch flex independently and individually.

A still further object of my invention is to provide a construction for disconnect switch which is relatively inexpensive to manufacture and relatively simple to adjust.

Another object of my invention is to provide a disconnect switch structure which can be either operated by a hook stick or gang operated remote means from remote hydraulic, pneumatic or electrical means.

Still another object of my novel switch is to provide a structural arrangement wherein optimum contact pressure can be obtained.

A further object of my invention is to provide a disconnect switch having a plurality of blade fingers and a plurality of spring contacts which cooperate therewith to obtain a predetermined pressure between the blade fingers and the jaw tongue.

Another object of my invention is to provide a disconnect switch having a plurality of spring contacts attached to the jaw members which are made of high-strength, highconductivity, precipitation-hardened alloy such as beryllium copper.

Another object of my inventionis to provide stationary spring contact means for a disconnect switch which will not anneal the temperatures encountered by the switch, even under short circuit currents within a period of, for example five or ten seconds.

A further object of my invention is to provide a disconnect switch in which contact pressures of substantially uniform value are obtained over a plurality of spot contacts.

Another object of my invention is to provide switching means in which the contact pressure will remain constant for the life of the switch.

A further object of my invention is to provide a knife type disconnect switch which is inexpensive to manufacture and which can easily be inspected to insure uniformity and which requires no special skill or care in assembly or alignment.

A further object is to provide a disconnect switch having sequential blade movement in which the outer pair of blades in each unit opens ahead of the inner blades.

A still further object of my invention is to provide a novel switch which only requires half the normal switch operating eifort to open.

A further object of my invention is to provide a novel disconnect switch which may be gang connected for use to disconnect aluminum pot lines from rectifiers.

These and other objects of my invention will be apparent from the following description when taken in connection with the drawings in which:

Figure l is a perspective view of my novel disconnect switch shown in open position. This disconnect switch is adapted for hook stick operation and therefore is provided with a short circuiting latch. However, as will be apparent from the following description, the construction and features of the hook stick operated switch are identical to those of the disconnect switch which is to be gang operated.

Figure 2 is a side view of my novel disconnect switch. The switch of this figure is similar in construction and features to the switch shown in the perspective view of Figure 1 and varies therefrom only in the construction of the handle and its attachment to the blades.

Figure 3 is a view taken in the direction of the arrows 33 of Figure 2. This figure is an end view of my novel disconnect switch and shows the bellville spring washers used at the hinge end of the blades in order to permit rotation thereof while maintaining good contact pressure.

Figure 4 is a view taken in the direction of arrows 44 of Figure 2. This figure shows a top view of my novel disconnect switch and illustrates the connection of the handle to the inner and outer blades so as to achieve sequential blade movement. This figure further illustrates the manner in which the switch blades are sandwiched between the spring contacts and the jaw tongue for contact engagement therewith.

Figure 5 is a side view of Figure 6 of my novel switch and illustrates the manner in which the blade handle may be connected to linkage mechanism in order to operate the switch from a remote hydraulic, pneumatic or electrical means. In a preferred embodiment, the switch is operated from an electrical motor operating a common shaft in order to achieve gang operation to a plurality of switches.

Figure 6 is a perspective view showing a multiple switch arrangement utilizing the novel disconnect switches of my invention. In this figure, the plurality of switches are simultaneously operated through an electrical means.

As above noted, the hook stick operated switch of Figure 1 and the switch illustrated in the various views of Figures 2, 3 and 4, adapted for gang operation, are similar in construction and hence, identical numbers will be used to identify similar parts. Since the switch is symmetrical about the center line indicated in Figure 4, the components on the right or upper portion of the switch will be designated by the numeral indicating its lower or left hand corresponding components.

The switch is mounted on a rectangular base 10 of insulating material such as slate, ebonized asbestos, etc., which is provided with appropriate openings 11 to secure it to a proper mounting. The switch may also be mounted on porcelain insulators which are, in turn, bolted to a steel base. Openings at the upper right and left hand ends of the insulation base 10 are provided to receive the plurality of terminal connections 12 and 13 which in turn are provided with proper openings 14 and 15, respectively, for electrical attachment to the load and line.

The jaw member 18 is an integral unit comprising a heavy center base block 26) which is seated on the base 10, two vertically extending members 21 and 22 to receive spring contacts, hereinafter more fully described, and downwardly extending terminal members 12, heretofore described.

Base member 10 is provided with appropriate openings 30 to receive bolts 31 which pass therethrough and are securely attached in the threaded openings 25 in the jaw members 18. The bolts 31 are provided with fiat washers 32 and lock washers 33 to insure that the jaw member 18 is firmly and permanently secured to the base member 10.

At the hinge end of the switch, the hinge member 46 is provided with downwardly extending terminal members 13 which pass through appropriate openings in the insulation base 10, as heretofore noted. The hinge member 40 is provided with a base 41 which has appropriate threaded openings 42 to receive bolts 43 so that the hinge member 40 may be secured to the base 10.

The bolt members 43 are provided with appropriate fiat washers and lock washers 44 and 45 in the same manner as bolts 31.

The hinge member 40 is also provided with upwardly extending members 48 which are provided with an opening to enable the blade members -61 to be rotatably mounted thereon.

The hinge member 48 is sandwiched between the inside blade 61 and the outside blade 6 A screw 62 threaded on its ends 63 and 64 is positioned through the sandwiched combination of the outer switch blade 6i), the hinge member 48 and the inside switch blade 61. A pair of bellville spring washers 65 and 6e are positioned S *concentric with the screw member 62 'and lfeld rin position by means of nuts 67 and 68.

With this arrangement, the switch blades 60.and 61 are able to pivot or rotate about the hinge member 48 and still be able to maintain electrical contacttherewith. That is, current will flow from the jaw end through the switch blade to the hinge end thereof, passing' 'through'the hinge member 48, bases 41 and out'throughthe terminal connectors 13. Thus, the blade members are. able-to rotate about the axis of screwmember 62' into-and out ofengagement with the center jaw tongue 2fi and the plurality of spring contacts associated therewith.

As seen at the left hand endof Figures 2 and: 4, *the plurality of spring contacts 70 and 71 are secured to the upright portion 21 of the jawmemberilS onthe'inside and outside of the switch, respectively. Thus, as best seen in Figure 2, the plurality otspring contacts 70, a, b

' and 0, etc., are secured to'the jaw member21 alongthe 'diagonal line parallel touppersaedge. These spring Econtacts 70 are individually secured 10.12h651j2lW member 21' by means of bolts 73.

Hence, with this. arrangemengxeach' of theistationary contacts or spring contact fingers 70willbe 'able;to;-flex independently and individually; irrespectiverof Lthe'. position of the other contacts.

The blade. members 66 and 61:areislottedaseindicated at 75, 76, 77,. 73,79 in order ,toyform a'plurality of fingers 80:1,8'30, 89d, etc. Each of the fingers -80 joflthe blade 60, which form the movable .contact withsthis 'connect switch, are provided with ,spherical radius. con- .tact buttons' 99 and 91.

:It will be noted .thattheinside blade'61isv constructed .in-substantially the samemanner as notedfor theroutside blade 69. That.is,.it too.is provided with aplurality: of .parallelhorizontal slots forminga pluralitywof contact .flfingers 81 to. act as the movable.contacts;for-::engagement with the stationary contacts.

.The plurality of spherical radiuscontacts-90 located onthe outside of the outside bladetiare positionedfor .engagement'with the vflat surface of the spring contacts 70 and .the plurality of spherical radius contacts 92 .located on the inside surface of the inside. blade-61am 1 positioned for engagement with .ThC-fiQtmSUI'fHCQ-ZOII the spring contact 71.

The plurality I ofspherical. radius. contacts -91.-.1ocated on the inside surface of the outside'blade-fit),.andihe plurality of spherical radiuscontactsflS located on the outside surface of the inside blade 61 are positionedfor engagement With-the respective parallel surfaces of..the

- break tongue 29.

It will be noted that the surfaces-101 and idiot-the break tongue 29 are. drawn copper'bars. brazed .(silver soldered) intoislots inthe heavy blocklt). .The, sur- .faces' 101 and 12ot the drawn copper-barsare .very

.. accurate (i; e. flat and parallel) to-insurethat. they are parallel to each other in order to enable a goodrcontact tobe madebetween.:the spherical radius conta'cts of the switch blades 63 61 and the break tongue 20. Hence, these surfaces 101 and 1432 need: no machining.

It will be not'ed'that heretofore, switch blades of the prior art construction were embossedoncoined-on dia- .metrical opposite sides in order to-obtain protrusions which would act :as contact buttons for the switch-blade. However, inthis process, it was necessary'to reduce the' cross-sectional area 'of the 'biaddimme'diately adjacent the contact button" which resulted' in excessive temperature rise during short circuit conditions due to the concentration of the'h'eat within aconfined' area.

'That is, the constrictions not only increase the heat gen- 70 erated but also limited the heatflow and thereby resulted'in' the -increase temperature 'rise of "the coined contact sp ot.

"'Eu'rthermorejsince the coined contacts 'wereon diame'tricaloppositesides of' the switch bladej-there was an iiextremet concentration: of the heat i generated to :thereby -::cause. possible. damage to. the blades.

LHoweveriin the arrangement illustrated in the figures, ":thecontacts of the switch blade arejcreated by a forming operation ratherthan a coining operation and hence, are

created without'the necessity of reducing the cross-sec- :tional area of the blade and furthermore may be spaced apart; .alongithe longitudinal axis of the blade. This 'Ieadily overcomes all of the disadvantages encountered 10 with the prior art method of making contact buttonson the switch blade .and it is fully described and claimed in v.copending application Ser. No. 315,620, filed October '20, 3,1952.

"Withthe novel arrangement above described, the 'plu- '-Iality' of cooperatingcontacts can operate individually and independently. For example, the engagement ofthe spring contact 70a with thespherical radiusvcontact 900: on the blade finger 80a'will be able .to fiex so as to enable the spherical radius buttons 91a, positioned on the .20 "inside surfacexofthe-switch blade 6l,to engage the outer vertical; surface 162" of theheavy center jaw tongue '20.

' 'In'hke manner, all of the other spring contact members 70will be able to exert a separate. and independent pres- 'sure on their respective blade fingers and associate spherical radius contacts 91.

Itwillrbe noted that the identical condition exists for the blade 61tand its associated spring contacts 71 and spherical radius contacts 92 and 93.

This contact pressure exerted by the plurality of spring acontacts70 and 71 is caused by the cantilevered stress ximposed thereon when the'switch blades 6% and 61 sandwich between the contacts 70 and 71 and the heavy center cjaw. tongue 20.

As-heretoforenoted,tthe contact surfaces on the jaw member: '18, which comprises the two outside vertical .fextensionsi 21 and'the-heavy center jaw tongue 20, are that and parallel. 'As noted in copending application Ser. No.: 315,620, filed October 20, 1952, the vertical extentions: 21 are accurately positioned from the heavy center 40 jaw tongue 20 by meansof spacers. The spacers separating theseztwo units may be accurately machined to insure that these contacting. surfaces are positioned a predetermined distance from each other.

Furthermore, the novel means of creating contact buttons on thenswitchblade, that is by means of a forming operation rather than a coining operation as clearly :set forth in'the' above mentioned application Ser. No.

3'15,6'20,'filed'October 20, 1952, permits an accuratepredetermined contr'olof the transverse dimension from the top of the contact button on one side of the blade from the top ofthe contact button on the opposite side of the switch blade. That is, the accurate length of the spacer plus-the fact that the contacting areas of extensions I 211 and 21 are" fiat and parallel, and thefact that'the transverse-dimension of the blade member can be accurately controlled and measured, allows and permits a careful-control of the contact pressure.

Thus, it is possible to obtain a predetermined 'cantilevered-s'tress on the spring contacts 7e and 71 due to ,:theaccuratedimensioning and spacing, as above-noted. Furthermore, the plurality of spring contacts 76 and '71 are made from.a high-strength, high-conductivity, precipitation hardened alloy such as beryllium copper which is not subjectto annealing at temperatures encountered in this switch.

Accordingly, it is possible to obtain contact pressure on the plurality of spot contacts which is readily and carefully controlled and in which'the pressure is fairly uniform on all the contacts.

Furthermore, the contact pressure will remain substantially constant for the life of the switch.

- It will be notedthat the switch blades 6t3-61 are provided with anuppermost' finger 80f31f. As seen in Figure 2, the jaw of'the remaining contact fingers -8% a, b; 8.0c', 89d and 80e are in a diagonal line where- 7 as the-last finger blade and the associated part of inside blade 61 extends from this diagonal line. This ex-' tended blade finger 80 is provided with three spherical radius contact buttons whereas the other blade fingers are provided with only two contact buttons, 90 on the outside of the blade and 91 on the inside of the blade.

The blade finger 801 has the outside spherical radius contact 90 and the inside spherical radius contact 91 for engagement with the spring contact 70f and the break tongue 20, respectively.

The third spherical radius contact 94 is positioned for engagement with the spring contacts 70g and 71g. These additional contacting surfaces between the spherical radius contacts 94 and 95 on the switch blade and 61 with the additional spring contact g and 71g forms an auxiliary or arcing contact to take the slight arc that occurs when the current is transformed from the switch to some other piece of equipment such as a circuit breaker.

Due to the fact that the radial distance between the spring contact fingers 70g and 71g to the pivot point 62 of the switch blade 60 and 61 is greater than the radial distance of the spring contact 70a and 71a engagement with the former cooperating contacts 70g, 94, will occur after the engagement with the latter cooperating contacts 70a, a, 91a, 80a when a switch is moved from the open position of Figure l to the closed position of Figure 2.

Also, due to the fact that the radial distance progressively increases between contact engagement of the spring contact 70a, 71a up to the spring contacts 70g and 71g, the contact engagement between the cooperating contacts 70g, 94, 80 and 71g, 95, 81 will occur before disengagement of the cooperating contacts between 70a, 90a, 80a and 71a, 92a and 81a. Hence, the cooperating contacts associated with the spring contact 70g and 71g will act as auxiliary contacts to take the slight are that occurs when a current is transferred from the disconnect switch to some auxiliary piece of protective equipment such as a circuit breaker.

The blade handle is a triangle member with three hole openings 101-102-103. The embodiment shown in Figures 2, 3 and 4 is provided for attachment of the blade handle 100 to linkage mechanism controlled by motor operation, as hereinafter more fully described in connection with Figures 5 and 6.

When a switch blade is moved from the closed position of Figure 2 to the open position as illustrated in Figure l, the blade handle 100 will be moved to the dotted position seen in Figure 2.

With my novel structural arrangement sequential blade movement is possible in which the outer pair of blades of 60-60 open ahead of the inner pair of blades 61- 61'. With this blade movement, which is obtained in both the gang operated switch and the hook stick op-v erated switch, it is possible to obtain openings of the switch with only half of the switch operating effort.

This is accomplished as follows:

The pin is positioned through appropriate openings in the blades 60-61, (Sty-61. The openings in the in ner blades 61-61 are considerably larger than the diameter of the pin 165, whereas the openings in the outer blades 60-60 are substantially of the same dimension as the diameter of the pin 105.

Thus, it will be seen that the pin 105 which passes through the switch blades 60-61, opening 102 in the blade handle 100, and the switch blades 60'-61 will have relative movement to the two inner switch blades 61-61 and no relative movement with respect to the outer two blades 60-60.

Thus, it will be seen that an upward pull on the operating handle 100 would initially exert a force through the pin 105 to only the outer switch blades 60-60. ,That is, not until the pin 105 engages the upper circumference of the enlarged opening in the initial switch blades 61-61 will force be transmitted to these blades.

Hence, with this novel construction it is possible to exert all of the opening force on the outer switch blades 60-60 to thereby enable them to break with their associated spring contacts 70 and 70' before movement of the inner blades 61-61 is initiated.

Pin means is provided with an initial pivot for the operating handle 100. The pin means 110 passes through the opening 103 of the handle 100 and links in appropriate openings only the inner switch blades 60-61. The openings in the inner blades 61-61 are elongated slots of substantially the same width of the diameter of the pivot 110.

Hence, when the handle 100 is initially moved from the solid position toward the dotted position (as seen in Figures 2 and 5), it will pivot about the pin 110 causing the pin 105 to engage only the outer switch blades 60-60' due to the fact that the openings in the inner switch blades 61-61, which receive the pin 105, are larger than the diameter thereof.

Hence, with this novel construction, it is possible to obtain sequential blade movement by which a force exerted on the operating handle 100 will initially be transmitted to the outer blades 60-60' to enable them to open ahead of the inner blades 61-61.

The high current disconnect switch shown in Figures 2, 3 and 4 is adapted for gang operation in the manner shown in the detailed Figure 5 and in the prospective view of Figure 6. As will hereinafter be apparent the linkage mechanism required for the gang operation of this switch will form a rigid member to hold the disconnect switch in closed position, that is, even on the appearance of a short circuit current.

The blow out effect due to the magnetic forces will be counteracted by the linkage mechanism to thereby prevent the switch from opening. However, when the high current disconnect switch is to be operated by a hook stick, as seen in Figure 1, it will be necessary to provide a short circuit latch to insure that the switch will not Open under the magnetic forces created by a short circuit.

The manner in which a plurality of high current disconnect switches, as seen in Figures 2, 3 and 4 may be connected and assembled for gang operation, is shown in Figures 5 and 6.

As heretofore mentioned, the operating handle 100 is secured to the switch blades by means of connecting pins 105 and 110, which pass through appropriate openings 102 and 102 of the operating handle. The third opening 101 in the operating handle 100 is provided to receive a pin 111 to enable connection of the clevis or yoke 112 to the operating handle 100. Thus, the pin 101 enables a hinged or rotatable connection between the U-shaped connecting member 112 and the operating handle 100.

The U-shaped connecting member 111 has an insulating link 113 permanently secured thereto in any desirable manner. The clevis or yoke 114 is rotatably connected to the operating crank or operating arm 115 by means of pin 116. The crank 115 is provided with a clamping end and clamp 121 which permanently secure the link 115 to the main operating shaft 125 by means of bolt and nut connections 126-127.

As best seen in Figure 6, the main operating shaft 125 is journaled in the plurality of bushings 130 which are permanently secured to the main wall spot 131. Initial counterclockwise rotation of the main operating shaft 125 in the plurality of bushings 130 will cause counterclockwise rotation of the plurality of cranks 115 which are rigidly secured thereto by means of the bracket 120-121 and bolt and nut connections 126-127.

This force will be met through the pin connection 116 to the integral unit of the clevis 114, insulated link "11131andfclevis' 112. "This force'in turnwill be transmittedirom this linkage through the pin 111 to the ophousing 141 positioned above the motor housing 140 provides aprotection for the gear mechanisms which will .enable force to betransmittedfrom the motor 140' to the ..-main operating shaft 125.

..As. thusseen .in Figure .the shaft 142 is rotated by the electric motor" 140' positioned in housing.

A standard pivotal gear arrangement 143-144 may be provided to transmittherotational force of the motor shaft 142 tothe. main operating shaft 125 which is positioned perpendicular thereto.

Thus it will be seen that control over the blade directionalmotor 125 will enable the operator to simultaneously open the plurality of high current disconnect switches.

In summary, I have provided a novel high current disconnect switch in which the contact pressure on the plurality of cooperating contacts can be readily and carefully controlled and remain substantially constant for the life of the switch and in my novel disconnect switch a plurality of slots are provided in the switch blades in order to form a plurality of jaw fingers which act as the movable contacts. By providing a plurality of resilient stationary contacts, it is possible to obtain a structural arrangement wherein all of the plurality of cooperating contacts for the high current disconnect switch will flex independently and individually.

Furthermore, the resilient stationary contacts 70 70 7171 have a predetermined cantilever stress placed thereon in order to obtain predetermined pressure between the jaw fingers and the jaw tongue.

My novel disconnect switch links itself to application and control by either hook stick or gang operation and for either type of operation, has sequential blade movement wherein the outer blades open ahead of the inner blades, thereby half the operating efiort.

In the foregoing, I have described my invention only in connection with preferred embodiments thereof. Many variations and modifications of the principles of my invention within the scope of the description herein are obvious. Accordingly, I prefer to be bound not by the specific disclosure herein but only by the appending claims.

I claim:

1. A high current disconnect switch comprising "a pair of switch blades, a jaw tongue and a plurality of spring contacts; said jaw tongue being a single relatively heavy member with parallel sides; said switch blades being rotatably mounted on said disconnect switch and having a hinged end and a jaw end, a plurality of slots running parallel to the longitudinal axis of the said switch blades at the jaw end thereof to form a plurality of blade fingers, each of said blade fingers having at least one spherical radius contact on one side thereof for engagement with said jaw tongue and a second spherical radius contact on the other side thereof for engagement with said spring contacts, a spring contact individual to each of said blade fingers for biasing said blade fingers into engagement with said jaw tongue; said switch blades connected to close over and touch the parallel sides of said jaw tongue.

2. In a disconnect switch having an open and closed position comprising a jaw tongue, a switch blade and a "plurality lof s'pri'n g cont-acts, said switch blade "sandwiched .between's'aid jaw tongue and'said plurality ofjspring "contacts'when 'said disconnect switch is in said'clos'ed posi- "tion, said switch blade having a plurality of blade fingers,

each of said blade fingers cooperating with atleast one of said spring contacts to enable the combination to flex independently and individually.

3. In a disconnect switch comprising a switch blade, a jaw'tongue and a plurality of spring contacts and having a first and second terminal, said plurality of spring contacts and said jaw tongue secured to'said second terminal, said switch blade movably mounted on said first terminal for engagement and disengagement with said plurality of spring' contacts and said 'jaw .tongue, said'switch blade having a plurality of blade fingers; positioned for. individual engagement with each of said plurality of spring contacts when said blade is in said. engaged position,

I said blade sandwiched between said jaw tongue and'said plurality of spring contacts when in said engaged position to thereby permit said plurality of spring contacts and blade fingers to flex individually and independently.

4. In a disconnect switch having an open and closed position comprising a jaw tongue, a switch blade and a plurality of spring contacts, said switch blade sandwiched between said jaw tongue and said plurality of spring contacts when said disconnect switch is in said closed position, said switch blade having a plurality of blade fingers, each of said blade fingers cooperating with at least one of said spring contacts to enable the combination to flex independently and individually, said plurality of spring contacts positioned at an angle to the transverse axis of said switch blade to enable disengagement of some of said blade fingers from said spring contacts prior to the disengagement of other blade fingers from other of said spring contacts.

5. In a disconnect switch having a jaw tongue and a switch blade for engagement therewith, a plurality of spring contacts positioned parallel to said jaw tongue, said switch blade comprising a plurality of jaw fingers for individual cooperation with each of said spring contacts, said switch blade positioned between said jaw tongue and said plurality of spring contacts when said blade is in said engaged position, said plurality of cooperating contacts comprising said blade fingers and said spring contacts flexing independently and individually.

6. In a disconnect switch having a jaw tongue and switch blade for engagement therewith, a plurality of spring contacts positioned parallel to said jaw tongue, said switch blade comprising a plurality of jaw fingers for cooperation with each or" said spring contacts, said switch blade positioned between said jaw tongue and said plurality of spring contacts when said blade is in said engaged position, said plurality of cooperating contacts comprising said blade fingers and said spring contacts flexing independently and individually, spherical radius contacts on one side of said blade fingers for engagement with said jaw tongue, spherical radius contacts on the other side of said blade fingers for engagement with said spring contacts.

7. In a high current disconnect switch comprising a pair of switch blades, a jaw tongue and a plurality of spring contacts; said pair of switch blades being formed with a plurality of blade fingers, each of said plurality of blade fingers having a cooperating spring contact associated with said blade fingers of a first switch blade and a second set of said spring contacts associated with the blade fingers of a second switch blade, manual means effective to cause disengagement of said first switch blade from said first set of spring contacts before disengagement of said second switch blade with said second set of said plurality of spring contacts.

8. In a disconnect switch having an open and a closed position, a fixed contact and a plurality of cooperating contacts, said plurality of cooperating contacts comprising blade fingers forming a part of a switch blade of said disconnect switch and a plurality of spring contacts for biasing said blade fingers into engagement with said fixed contact, each set of cooperating contacts comprising said spring contacts and said blade fingers flexing independently and individually.

9. In a disconnect switch having an open and closed position comprising a jaw tongue, a switch blade and spring contacts, said switch blade being movably mounted with respect to said jaw tongue for movement into and out of engagement with said jaw tongue and said spring contacts, said blade member having a plurality of blade fingers for individual engagement with said spring contacts and said jaw tongue, said spring contacts cooperating with said blade fingers to insure fairly uniform contact pressure between said blade fingers and said jaw tongue.

10. In a disconnect switch comprising a switch blade, a jaw tongue and a plurality of spring contacts and having a first and second terminal, said plurality of spring contacts and said jaw tongue secured to said second terminal,

said switch blade movably mounted on said first terminal for engagement and disengagement with said plurality of spring contacts and said jaw tongue, said switch blade having a plurality of blade fingers, positioned for individual engagement with each of said plurality of spring contacts when said blade is in said engaged position, each of said blade fingers having at least one spherical radius contact for engagement with said jaw tongue and at least one spherical radius contact for engagement with its as sociated spring contact, said blade sandwiched between 12 said jaw tongue and said plurality of spring contacts when in said engaged position to thereby permit said plurality of spring contacts and blade fingers to flex individually and independently.

11. In a disconnect switch having an open and closed position comprising a jaw tongue, :a switch blade'and a plurality of spring contacts, said switch blade sandwiched between said jaw tongue and said plurality of spring contacts whensaid disconnect switch is in said closed posi tion, said switch blade having a plurality of blade fingers, each or" said blade fingers cooperating with at least one of said spring contacts to enable the combination to flex independently and individually, said plurality of spring contacts positioned at an angle to the transverse axisof said switch blade to enable disengagement of some of said blade fingers from said spring contacts prior to the disengagement of other blade fingers from other of said spring contacts, and to permit engagement of said some of said blade fingers with said spring contacts prior to the engagement of said other blade fingers with said spring contacts.

References Cited in the file of this patent UNITED STATES PATENTS 1,925,454 Cannon et al May 7, 1912 1,935,516 Musgrave Nov. 14, 1933 2,226,386 Ramsey Dec. 24, 1940

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