US1700884A - Switch mechanism - Google Patents

Description

Feb. 5; 1929. 1,700,884

D. R. DAVIES SWITCH MECHANISM Filed Nov. 21, 1925 2 Sheets-Sheet 1 INVENTOR WITNESSES:

*5 4 777% Dav/a Peg ina/dDa v/es" M I W ATTORNEY Feb. 5, 1929. 1,700,884

D- R. DAVIES sw mcn MECHANISM Filed Nov. 21, 1925 2 Sheets-Sheet 2 WITNESSES: IINVENTOR I .45 f .Da W0 Peg/na/albwes ATTORNEY Patented Feb. 5, 1929.

' UNITED STATES 1,700,884 PATENT oFFicE.

DAVIDREGINALD DAVIES, OF MANCHESTER, ENGLAND, ASSIGNDR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

SWITCH MECHANISM.

Application filed Novemberfil, 1925, Serial No. 70,541 and in Great Britain November 28, 1924.

My invention relates to electrical switch gear of that particular type which comprises two or more separable portions, the respective devices in which are adapted to be electrically connected together or disconnected by means of plug and socket contacts which are caused to engage or disengage one another when one portion of the switch gear is moved towards or drawn out from the other. Thus, for example, the plugs may constitutc isolating switches for a circuit-breaker which may be mounted on one of the portions of the gear.

The invention further particularly relates to switch gear of the type above set forth in which alternative connections are adapted to be made by the plug and socket contacts, for example, switch gear in which duplicate sets of bus-bars are adapted to be selectively connected to a cable, feeder or the like by means of an oil circuit-breaker.

Heretofore, the selective connection has been obtained by the employment of a set of removable plug contacts such as illustrated in the co-pendin'g application of Theador C. Christianson, Serial No. 644,023 (Case No. 11,146) and assigned to the Westinghouse Electric & Manufacturing Company. The plugs can be transferred from the part to another of oneportion of the switch gear so that when the latter is closed the plugs will engage any one of a plurality of sets of sockets pertaining to the devices which it is desired shall be connected with the oil circuit breaker for example.

lVith such type of switch gear, it will be readily appreciated that it is possible to move certain of the plugs into such positions as will result in some of each of the alternate connections being established when the switch gear is moved to close the connections. Thus in a three-phase switch gear with duplicate bus-bars it is possible to move one or two of the plugs into such positions as will result in one or more of each set of bus-bars being connected to the oil circuit breaker simultaneously and such a condition is obviously undesirable. It has been proposed to provide in various ways, means for preventing the possibility of the establishment of some of each of the alternative connections.

According to the present invention a single set of plugs is provided fixed to a part of one portion of the switch gear which partis ca- ,pable of movement with respect to the remainder of said portion so that the plugs can be brought as desired into any one of a plurality of positions wherein they are in alignment with one of a corresponding number of sets of cooperating sockets provided in the other portion of the switch gear to enable the required connections to be selectively established when the portions of the switch gear are moved together or closed.

In switch gear of the iron-clad or armoured type, the arrangement is preferably such that when the part carrying the plugs is moved from one posit-ion to another the conductors connecting the plugs with other devices, such as the terminals of an oil circuit breaker, are at no time exposed. For this purpose said conductors may be flexible and the relatively movable parts of the switch gear portion telescopically arranged with respect to one an.- other.

In the arrangement according to the invention it will be appreciated that it is impossible to close the switch gear with the plugs in such positions as will result in one or more of each of the alternative connections being made. Moreover, since the plugs are not required to be detached and moved from one position to another they may be made of less weight and of simpler construction. Similarly, the part of the portion of the switch gear which carries said plugs can also be made smaller and of simpler construction. The total space which the switch. gear occupies may also be reduced owing to the fact that it is not necessary to move the portions suflioiently far apart to permit detaching and transferring the plugs from one position to another as was necessary in switch gear of the ty ie previously herein mentioned.

In general, it is an object of my invention to provide switch gear of the iron-clad, draw out type wherein the bus-bars and contact terminals connections are encased in housings filled with insulating compound and wherein the movable circuit breaker is pro vided with disconnect contacts, certain of which are movable with respect to the circuit breaker for selectively engaging fixed contact members connected to different sets of bus-bars.

Another object of my invention is to provide a draw out switch gear wherein all live conductors are rendered inaccessible regard less of the position of the draw out portion of the switch gear and without necessitating a separate enclosure or cell for the entire apparatus.

To enable the invention to be fully understood, an application thereof to iron dad or armoured three-phase switch gear having two sets of bus-bars will now be described with reference to the accompanying draw ings, in which Fig. 1 is a sectional elevation of the gear and Fig. 2 an elevation of the draw out portion thereof showing one form of raising mechanism for the movable portion or bonnet carrying the selector plugs.

Referring first to Fig. 1 the switch gear therein illustrated comprises in general a frame-work 1, carrying at the left hand end thereof the fixed support portion 2 of the switch gear and at the right hand end the movable support of draw out portion 3 thereof, said portion being arranged to slide horizontally upon rails and provided with mechanism not shown for drawing it in or out with respect to the fixed portion 2 of the gear.

The fixed support portion 2 of the switch gear comprises three compound-filled metal casings 4, 5 and 6, and a cable trifurcating box 7. The casing 4 contains three bus-bars 8 and the casing 5 contains three bus-bars 9 which may be exactly similar to the bus-bars 8. The bus-bars 8 are respectively connected to three sockets 1O constituting disconnect contact members which are disposed in a horizontal plane and located within tubes 11 of insulating material located in tubular extensions of the casing 4, as shown. The alternative bus-bars 9 are connected to three sockets 12 arranged in a similar manner to the sockets 10 but in a horizontal plane beneath them.

A cable or feeder 13 entering the trifurcating box 7 has three phase-conductors 14 which pass into the casing 6 which contains potential, instrument or other transformers 15, and are connected respectively to three sockets 16 arranged similarly to the socket 10 and 12 but in a lower horizontal plane.

The moving support portion 3 of the switch gear comprises a three-phase oil circuit breaker 17, each phase of which has terminal conductors 18 and 19, and a bridge member 20 the movements of which are effected through an operating rod 21 from the switch actuating mechanism 22, which may be of any desired form. The terminals 18 of the three-phase oil switch pass through a casing 23, from which project three plugs or contact terminals 24 surrounded in part by insulating sleeves 25, the plugs 24 being adapted to cooperate with the sockets 16 in the fixed portion 2 of the switch gear.

The terminals 19 of the oil switch 17 are connected through flexible conductors 26 with conductors 27 disposed in a bonnet or casing 28 and connected with three plugs 29 surrounded in part by insulating sleeves 25. The plugs 29 are adapted to cooperate either with the sockets 10 or with the sockets 12 in the fixed portion 2 of the switch gear, as desired. For this purpose the bonnet or casing 28 is provided with a downwardly extending metal tube 30 which has a telescopic engagement with a metal tube 31 projecting upwards from the head of the oil circuit breaker 17, the arrangement being such that the bonnet 28 may be raised or lowered so that it can occupy either of its limiting positions 29 or 29 or an intermediate position such as 29 the positions 29 and 29 being shown in dotted lines.

It will be understood that when in the upper position 29 the plugs can cooperate with 80 the sockets 10 and when in the lower position 29 they can cooperate with the sockets 12, whilst the plugs 24 cooperate solely with the sockets 16. \Vhen the plugs 29 are in the intermediate position they may cooperate with sockets 32 disposed between the armoured projections of the casings 4 and 5 which surround the insulating sleeves 11, for a purpose which will be hereinafter described.

Preferably, the flexible conductors 26 are surrounded by insulating tubes 33 and 34 which also have telescopic engagements with one another. For purposes of safety movable covers or cowls indicated at 11 may be arranged normally to close the ends of the tubes 11 and to be opened automatically up on closure of the switch gear, the covers pertaining to the sockets 10 or 12 with which the plugs 29 do not engage preferably re- 10o maining closed.

With the arrangement above described it will be understood that by means of the switch gear the cable 13 may be connected through the isolating switches comprising 105 the sockets 16 and plugs 24, the oil circuit breaker 17 and either of the selector switches constituted by the plugs 29 and the sockets 10 or 12 respectively to either of the set of bus-bars 8 or 9. To establish such connec- 110 tion it is necessary first to open the oil circuit breaker 17 next to close the switch gear so that the plugs engage the sockets in the desired manner, and then to close the circuit breaker.

When it is desired to change the connection of the cable 13 from one set of bus-bars to the other, it is necessary first toopen the circuit breaker, next to withdraw the movable portion 3 of the switch gear from the 120 fixed portion 2 thereof, then to raise or lower the bonnet 28 so that the plugs 29 are in alignment with the other set of sockets 10 or 12, again to close the switch gear, and finally to close the circuit breaker.

It will thus be appreciated that since the plugs are fixed in position and not detachable as heretofore it will be impossible to close the switch gear with some of the phases connected to one set of bus-bars and some 130 connected to the other set. Moreover the difficulty of moving the plugs from one position to anotherand the possibledanger involved in such action are avoided.

The bonnet or casing 28 containing the plugs 291nayj be raised or lowered in any convenient manner, one arrangement for the purposes beingillustrated in Fig. 2, to which reference is now particularly made. In. such arrai'igcment a vertical screw threaded shaft 35 is rotatably mountedbetween the head of the ,oilcircuit breaker 17 and a framework 36 which may extend across the movable portion 8 of the switch gear. A threaded nut 37 adaptedto cooperate with the screw-thread ed shaft 35 is afiixed to the bonnet or movable portion 28 carrying the plugs 29. A bevel wheel 38 secured. to the lower end of the shaft 35 and a cooperating bevel wheel 39 is secured to a. longitudinal shaft 40, provided with an operating crank 41 by the rotation of which it will be clear that the bonnet 28 may be raised or lowered between its limiting positions previously herein referred to. Instead of the screw and nut and bevel mecha nism just described, it will be understood that any other form of mechanism, such as rack and pinion, or worm and worm wheel, for example, may be employed.

The auxiliary sockets 82 which are located in a vertical plane in front of that containing the sockets 10, 12 and 16 may be connected to earth so that by moving the bonnet 28 to its intermediate position and partially closing the switch gear, the plugs 29 which normally cooperate with the sockets 10 and 12 can be connected to earth. Since thus only the plugs 29 and the terminals 19 of the oil switch are cart-lied, it is necessary, if it is desired to earth also the cable or feeder 13,

to provide an. extension piece for the plug 24 to enable it to make electrical contact with the socket 16, it being appreciated that the switch gear is not completely closed as the cart-hing sockets 32 are in advance of the sockets 10, 12, and 16. Such extension piece may comprise a combined plug and socket of appropriate length.

It will be understood to those skilled in the art that various interlocks may be provided to prevent undesirable or unsafe operation of the switch gear.

Although one form of an iron-clad switch gear having the invention applied thereto has been illustrated and described, it will be understood that the invention is not limited to such gear but is applicable to other switch gear of the draw out type in which alternative connections are required to be selectively made by means of plugs and sockets. It will be understood also that instead of one set of plugs and alternative sockets, two sets of plugs and a single movable set of sockets may be provided, although the former arrangement is preferred since for reasons of safety it is usual to connect the plugs with the terminals of the circuit-breaker and the sockets with the'bus-bars and-cable or feeder.

I claim as my invention I 1. Switch mechanism comprising. a plurality of fixed contact members anda switch device having a pair of terminals for engaging a pair of contact members and being bodily movable for withdrawing the terminals from the engagement with the contact members, one of the said terminals being movable with respectto the switch mechanism for selectively engaging the said contact members.

2.- Switch.mechanism comprising a pair of relatively movable supporting units, one of which carries a plurality of contact members and the other carrying a switch device having a pair of terminal members for engaging a pair of contact members, one of the said terminal members connected to the switch being movable with respect to the switch for selectively engaging the said 0011- tact members.

3. Switch mechanism comprising a pair of relatively movable supporting units, one of which carries a plurality of contact members and the'other carrying a switch device having a terminal movable with respect to the switch device for selectively engaging the said contact members.

4;. Switch mechanism comprising a pair of relatively movable supporting units, one of which carries a plurality of disconnect contact members and the other carrying a, circuit breaker having a disconnect terminal member movable with respect thereto for selectively engaging the said disconnect contact members.

5. Switch mechanism comprising a pair of relatively movable supporting units, one of which carries a plurality of disconnect contact members and the other carrying a circuit breaker having a pair of disconnect terminal members, one of which is relatively movable with respect to the circuit breaker for selectively engaging the said disconnect contact members.

6. Switch mechanism comprising a pair of supporting units, movable relatively in a horizontal plane, one of which carries a plurality of fixed disconnect contact members arranged in a vertical row, and the other unit carrying a circuit breaker and a vertically movable disconnect terminal member therefor for selectively engaging the said contact members, and means for moving the movable terminal member in a vertical plane to different operative positions.

7. Switch mechanism comprising a pair of supporting units movable relatively in. a horizontal plane, one of which carries a plurality of disconnect contact members arranged in superimposed horizontal rows, and the other carrying a circuit breaker having a plurality of disconnect terminal members arranged in horizontal rows, the terminal members of the row of terminals connected to the circuit breaker being simultaneously movable vertically and for selectively engaging the said contact members of different rows.

8. Switch mechanism comprising a frame having a horizontal guide way, stationary disconnect contact members fixed to the frame a circuit breaker mounted for hori zontal movement upon the guide way for movement toward and away from the contact members, and disconnect terminal members for the circuit breaker, at least one of which is adjustable vertically into registry with different contact members whereby the circuit breaker may be selectively connected to the contact members when moved toward them. i

9. Switch mechanism comprising a plurality of fixed contact members, and a circuit breaker movable bodily with respect to the contzct members and having a Vertically movable terminal for selectively engaging the contact members.

In testimony whereof, I have hereunto subscribed-my name this 29th day of October, 1925.

DAVID REGINALD DAVIES.

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