US1732713A - Electrical switch gear - Google Patents

Description

Filed Feb. 20, 1924 Z SIIQQtS-5h@t WITNESSES: I

ATTORNEY Oct. 22, 1929. T. c. CHRISTIANSON 1,732,713

ELECTRICAL SWITCH GEAR Filed Feb. 20. 1924 2 Sheets-Sheet 2 F/ig, 3.

INVENTOR Theodore C Omisf/omon ATTORNEY Patented Oct. 22, 1929 UNITED. STATES PATENT OFFICE THEODORE CHRISTIAN CHRISTIANSON, 0F MANCHESTER, ENGLAND, ASSIGNOB TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION 01 PENNSYLVANIA ELECTRICAL SWITCH GEAR Application filed February 20, 1924, Serial No.

My invention relates to electrical switch mechanisms and in particular to switch mechanisms of the kind or class wherein busbars, cables, contacts and other electrical conductors or devices are enclosed in metal casings. Such switch mechanism is commonly known as armoured or iron-clad switch mechanism and comprises, in general, one or more oil switches by means of which circuits carrying currents are made and broken and one or more other switches, such as isolating or selector switches, which are emloyed for establishing various connections but which are not adapted for making or breaking circuits when carrying heavy currents.

c The object of the invention is to provide in a switch mechanism of the kind above set forth an improved construction and arrangement of switch of the latter class, that is to say, a switch which is not required to break a heavy current and which may be advantageously employed for effecting alternative connections, such for instance, as is necessary in cases where alternative sets of bus-bars are provided, or where switching means are required for ear-thing different parts of the switch gear, such as the bus-bars orthe cable as is sometimes required for testing and other purposes. The improved switch may also be used for .eltecting other connections in the switch mechanism.

The improved switch, according to the invention is of the socket and movable plug or plunger type and the plug is removable from its socket, access to the plug being obtained through an orifice in the armouring or metal casing of the switch mechanism, the arrangement being such that said plug 1s removable from the switch gear and may, if required, be inserted therein at another place to complete a different circuit having similar terminals.

The invention may be employed with advantage in armoured switch mechanism of the type in which the oil circuit-breaker structure is normally fixed to, but susceptible of separation from, the fixed armoured structure housing, for instance, the bus-bars; it may also be employed with advantage in the so-called draw-out or truck type of switch mechanism, that is to say, switch mechanism wherein one 694,023, and in Great Britain March 8, 1923.

portion thereof,'such as the oil switch and associated conductors, is movable relative to another portion thereof, such as the chamber or chambers containing the bus-bars and other devices and wherein electrical connection between the portions of the mechanism is effected by means of isolating switches for instance, of the plug and socket type, which are operated by movement of one of said p0r-' move the truck back again to its operative po- I sition and finally to close the oil switch. In

other constructions, the contact members carried by the truck are arranged to connect, at all times, with both of the bus-bars and independently operable selector switches are provided by which one or other of the truck contacts may-be connected wit-h the terminalof the oil switch. The employment of switches according to the present invention in switch mechanism of this type permits change of connection from one bus-bar to the duplicate bus-bar to be made without moving the truck from its operative position.

In order that the invention may be clearl understood it will now be described with re -erence to the accompanying drawings as applied by way of example, to switch gear of the draw-out type, wherein Fig. 1 is a diagrammatic vertical section through one phase of a three-phase switch mechanism; and

Fig. 2 is an electrical diagram of the circuit conneptions for the apparatus shown in Fig. 1 an Fig. 3 is an enlarged front elevational view of the apparatus shown in Fig. 1.

Referring to Fig. 1, the apparatus includes mechanism containing the bus-bars, the sleeves 6, 7 and 8 project into sleeves 9, l0 and 11 located in bus-bar and cable chambers 12, 13

and 14, constituting the stationary cell as.

shown in the drawing. The sleeves 9, 10 and 11 contain metallic terminals 15, 16 and 17 having sockets 18 19 and 20 which are coaxial with corresponding holes 21, 22 and 23 formed in the annularcontacts 3, 4 and 5.

The three terminals 15 corresponding to the three phases are connected, each with one of the bus-bars 24 located in the chamber 12, the terminals 16 being similarly connected with a duplicate set of bus-bars 25 located in the chamber 13 while the terminals 17" are connected to the three-phase conductors of a cable 26. The contact members 5 are connected to three switch contact members 27 of A the oil circuit-breakers 1, the phase contacts 28 of which are connected bothto the contact members 3 and 4 as indicated by the conduc tors 31.

The phase terminals 15, 16 and 17 are adapted to be electrically connected to the corresponding phase contacts 3, 4 and 5, rev

s ectively, by means of the movable plugs 29.

ach of these plugs comprises a metallic rod having one end adapted to fit into one of the sockets 18, 19. or 20, the other end having, for instance, a conical portion turned thereon which is adapted to fit into the contacts 3, 4 and 5. i

An insulating handle 30. is provided by means of which a plug may be removed from an operative position and, if required, inserted in another operative position, it being unnecessary to open the truck for this purpose since the handle 30 projects through an opening in the casing to the exterior. The insulating handle 30 is turned preferably to nearly thesame diameter as the inside of sleeves 6, 7 and 8 in order to exclude moisture, dust and the like. Instead of providing a handle, the

lug may be connected by an insulating memher with a metal or other external member and may be operated electrically or mechanically elther directly 'or by remote control means, (not shown).

Plu 5 may also be provided of other type than t ose described above, adapted, to make connection between an external temporar circuit and anyone of the contacts 15, 16, 1 oriof 3, 4, 5, for such purposes as testing or earthing.

Referring to Fig. 2 the circuit connections are more clearly shown, the reference numerals indicating the same with reference to Fig. 1.

When it is desired to connect the cable 26 to one of the sets of bus- bars 24 or 25 and the truck has been moved in its closed position, three plugs are so inserted as to electrically connect the terminals 5 and 17, the three phase conductors of the feeder 26 being then connected to the switch contacts 27 .of the oil switch 1. Three more plugs are then inserted in either the terminals 3 and 15 or the terminals 4 and 16 according to whether it is desired to connect the feeder cable 26 to the bus-bars 24 or the bus-bars 25. In the drawings, the plugs are shown as connecting the terminals 15 and 3.

The oil switch 1 is then closed, whereupon the circuit is completed from the terminals 17 through the plugs 29, contacts 5, the switch contacts 27 and 28 of the oil switch, conductors 31, contacts 3, plugs 29, terminals 15 and thence to the bus-bars 24. If it is desired afterwards to connect the cable 26 to the busbars 25, the oil switch 1 is opened and the plugs are withdrawn from the terminals 3 and 15 and inserted in the terminals 4 and 16 and the oil switch is then reclosed. By employing an interconnecting switch (not shown) to enable the bus-bars to be temporarily connected in parallel, it is possible, with the above arrangement, to change over from one set of bus-bars to the other set without interrupting the power supply to the cable 26.

In order to prevent the removal or insertion of a plug while the oil switch is closed, a suitable interlock may be provided between the oil switch operating mechanism and the plugs. One form of such interlock is diagrammatically illustrated in Fig. 1 by means of a plate 32 which cannot be moved laterally into its open position to permit of the removal or insertion of a plug until the member 33 fixed to and rotating with the operating shaft 34 of the oil switch mechanism is in a position corresponding to the open position parts described of the switch contacts 27 and 28 as indicated in Fig. 2. 'Means may also be provided for I preventing the plugs being simultaneously connected to two sets of bus-bars at the same time. Thus, a shutter 35 may be provided which is movable about a hinge 36 and is such that it can cover either the openings into the sleeves '6 or the openings into the sleeves 7. The shutter cannot be closed against the side of the oil switch hood 2 if plugs are inserted in the contact members 3 and 4 simultaneously and it is not possible therefore to place the plate 32 in its closed position which owing to the interlock member 33 in turn prevents the oil switch being closed.

Shutters, (not shown), may also be provided which will automatically shroud the entrances of the sleeves in the fixed part of' the switch gear whenthe' truck is removed and in the truck structure when the plugs are removed.

' Any preferred system of measuring instruments and of protection may be employed in connection with the switch mechanism and improved plug and socket switches in accordance with the invention may be conveniently made use of in such a system.

Referring to Fig. 1, a current transformer for a current measuring instrument is diagrammatically illustrated at 37 while conductors 38 are led to potential transformers for voltage measuring instruments. Fig. 2

shows clearly the connections for the voltage transformer which is indicated at 39, the circuit being conveniently completed a through a plug and socket switch 40 of the type described. I

Plug and socket switches in accordance with the invention may be employed in ironclad switch mechanism, other than of the truck type and for other purposes than those herein indicated such as for connecting the various enclosed apparatus of the switch gear to earth or to testing instruments, suitable sockets and corresponding orifices in the armouring or casing bein provided so that by inserting one or more plugs or plungers into the appropriate socket any of such parts may be connected to earth or elsewhere as required. I

In some cases, it is desirable to arrange that the withdrawal of a plug from a socket should take place under oil or other insulating liquid. This can readily be effected by arranging that the axes of the plugs and sockets shall be inclined to the horizontal so that the sockets form receptacles for oil or other insulating liquid into which the plugs are inserted in a downward direction.

One advantage of the employment of the improved switch in iron-clad switch mechanism having duplicate bus-bars or other connections as hereinbefore described is that it can readily be seen,.by inspection, which set of bus-bars is connected to the oil switch without the necessity of opening the oil time. 1

In the case of selector switches more than two sets of bus-bars may be provided and the bus-bar chambers may be located either all on one side or some on one side and some on the other side of the oil switch. In some cases a short plug connected to earth and adapted to make connection only with one or other or both of the terminals of the switch .may be employed when it is desired to effect the earthing of a bus-bar or other conductor .connected to the switch terminal.

It will be understood that various modifications may be made in the construction of the improved switch as described and illustrated without departing from the scope of the invention.

I claim as my invention:

1. Switch mechanism comprising a pair of relatively movable terminal members having separate housings, and a plug member for connecting the said terminal members detachably connected to one terminal member and movable into contact with the other terminal member and accessible for operation from the front of the mechanism through an orifice in one of the housings.

2. Switch mechanism comprising a pair of relatively movable terminal members having separate housings, and a plug member for connecting the said terminal members detachably connected to one terminal member and movable into contact with the other terminal member and accessible for operation through an orifice in one of the housings.

3. Switch mechanism comprising a plurality of pairs of relatively movable terminal members, and a plug member adapted to be selectively secured to a terminal of any pair of terminal members .and movable into contact with the other terminal of the said pair of terminal members, a circuit breaker connected to one of the said terminal members and means for preventing disconnection of the said plug except when the circuit breaker is in open position. 4. Switch mechanism comprising a plurality of pairs of relatively movable terminal members and a plurality of plug members adapted to be selectively and detachably secured to terminals of any of said pairs of terminal members and movable into contact with the other terminals of said pairs of terminal members, a circuit breaker connected to one of the said terminal members. and means for preventing closing of the circuit breaker so long as two or more plugs are simultaneously secured to terminal members of certain pairs of terminal members.

5. The combination with a switch mecha- I nism having a fixed terminal and a circuit breaker having a terminal movable with respect to the fixed terminal, of a conductive plugdetachably connected to the movable terminal and movable into contact with the fixed terminal.

6. The combination-with a switch mechanisin having a plurality of fixed contact terminals and a circuit breaker having a plurality of terminals movable with respect to the fixed terminals, of a conductive plug member ada ted to be detachably connected to any of the said movable terminals and movable into contact with a selected contact terminal.

7. The combination with a switch mechanism having aplurality of fixed contact ter minals and a circuit breaker having a plurality of terminals movable with respect to the fixed terminals, of a plurality of conductive plug members adapted to be detachably connected to any of the said movable termi- 5 nals and movable into contact with selected contact terminals.

8. The combination with a switch mechanism having a plurality of fixed contact terminals and a circuit breaker having a plum rality of terminals movable with respect to the fixed terminals, of a conductive plug member adapted to be detachably connected to any of the said movable terminals and movable into contact with a selected contact terminal and means for preventing disconnection of the plug members except when the circuit breaker is in open position.

9. The combination with a switch mechanism having a plurality of fixed contact terminals and a circuit breaker having a plurality of terminals movable with respect to the fixed terminals, of a plurality of conductive plug members adapted to be detachably connected to any of the said movable terminals and means for preventing closure of the circuit breaker so long as two or more plug members are connected to certain of the said movable terminals.

10. The combination with a switch mechanism having a fixed cell provided with a con tact terminal and a movable circuit breaker device provided with an enclosure containing a terminal member, of a conductive plug member detachably secured to the-terminal member and accessible through an orfice in the enclosure for connecting the terminal member to the contact terminal.

11. Switch mechanism comprising a pair of relatively movable support members, a

plurality of terminal members on each support member, and a connecting member adapted to be selectively detachably connected to one of the terminal members on one support member and movable with the said support member into engagement with a selected terminal member on the other support member.

12. Switch mechanism comprising a pair of relatively movable support members, a

53 plurality of terminal members on each support member, and a connecting member adapted to be selectively detachably connected to one of the terminal members on one support member for engaging a selected terminal member on the other support member, the connecting member being operable from the outer side of the first said support member.

In testimony whereof, I have hereunto subscribed my name this twenty-third day of January, 1924.

- THEODORE CHRISTIAN CHRISTIANSON.

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