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US1565287A - Electric switch gear - Google Patents

Electric switch gear Download PDF

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US1565287A
US1565287A US753375A US75337524A US1565287A US 1565287 A US1565287 A US 1565287A US 753375 A US753375 A US 753375A US 75337524 A US75337524 A US 75337524A US 1565287 A US1565287 A US 1565287A
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Prior art keywords
sockets
shaft
plug
main switch
busbar
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Expired - Lifetime
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US753375A
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Mirrey James
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A Reyrolle and Co Ltd
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A Reyrolle and Co Ltd
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02BBOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER
    • H02B11/00Switchgear having carriage withdrawable for isolation

Definitions

  • This invention relates to electric switchgear and has particular reference to switchgear used in connection with duplex busbar systems.
  • switchgear instead of the indicating mechanism being operated by the insertion of the plug, means are provided whereby the mechanism can be set to indicate a selected position of the plug and also to prevent the insertion of the plug in any other than such selected and indicated position.
  • the insertion of the plug in the proper position locks the indicating mechanism and its setting level' or other operating mechanism.
  • the setting lever and indicating and locking mechanism are on the movable or drawout portion of the switchgear and preferably there is provided on the xed or busbar portion one or more switches controlling auxiliary circuits, such switches being operated by the setting lever in accordance with its position when the movable portion of the gear is moved in or out.
  • switches controlling auxiliary circuits such switches being operated by the setting lever in accordance with its position when the movable portion of the gear is moved in or out.
  • auxiliary circuits and switches one for synchronizing or like purpose and the other :tor giving a remote indication of the position of the plug say by means of a lamp, semaphore or other signal.
  • the setting lever is connected to the indicating and locking mechanism through a spring or like yielding coupling interposed at some suitable place to prevent the possibility of damage through rough handling.
  • Figure 7 is a vertical section of the setting and indicating mechanism of Figure 6 drawn to a larger scale
  • Figure 8 is a cross-sectional plan on the line 8 8 of Figure 7 drawn to a larger scale than that figure.
  • FIG. 6 will iirst be refered to as illustrating a known type of switchgear to which the invention is applied.
  • A is a portion of the fixed part of the gear and comprises socket connections at B and C to duplicate busbars and another socket connection at D say to a feeder.
  • the movable or draw-out portion indicated as a whole by the letter E comprises a main oil-break switch in its tank F, a plug connection G cooperating with the socket connection D and socket connections H and J which, by means of a removable plug K can be made to cooperate with either of the busbar socket connections B or C.
  • These parts are well known in themselves and it will be understood that the movable portion E can be racked in and out and that the position of the removable plug K determines which of the busbars is selected for service and joined to the main switch.
  • connection L between the two sockets H and J is made tubular and contains within it a rotatable metal shaft having transverse holes L2 and L3 formed in it at levels corresponding to the centre lines of the sockets H and J.
  • the holes are at an angle so that when one (L2) is in line with its socket H the other (L3) is not in line With its socket J.
  • the removable plug K is formed with a pin or projection K which can enter the hole in the locking shaft L when such hole is in alignment With the socket.
  • the plug K can only loe inserted properly into the socket H or the socket J when the shaft L is turned into the correct position.
  • the shaft L is provided with an eX- tension L4 preferably of insulating material, upon which is mounted an arm or bracket L5 carrying an arc-shaped indicating plate M Working in conjunction With a Window or opening Mv through which the indications on the plate M can be read.
  • a bell crank lever N one end ot which is pivoted to a handle or operating lever 0 and the other end pivoted to a link O parallel to the operating lever O and joined to it by another bell crank lever N so that the levei (l moves parallel to thelink O.
  • Stops l) and P provided to limit the movement ot the operating lever O in each direction and round the upper part olf the shaft L LI is a coiled spring R which tends to rotate the shaft into the position shown in Figures 2 and i Where the indicating plate M occupies a central position in. relation to the window M and the shatt L is in such a position that the removable plug cannot be inserted in either of' the sockets H or J.
  • the operating bar O Will depress the handle S of a switch or switches S and cause them to close the circuit or circuits which they control. Sin'iiiarly it the shaft L It be rotated so that the operating lever O lies against the stop P the position ot the parts Will be as shown in Figures 3 and the pin K ot the removable plug ifi being allowed to enter the hole L and the indicator M displaying through the Window M the words Bottom plug in.
  • the mechanism is in this position the racking in oit' the movable portion of the sivitchgear will cause the operating lever O to depress the handle S2 of the switch or switches S3 and the circuits controlled by those switches will be closed.
  • the handles S S2' are spring-controlled so that the switch opens when the operating bar no longer depresses the handle. Further the arrangement is such that atte' the bar O has depressed the handle S or S2 it can slide over it keeping it down but putting no l'urther strain on the closed switch.
  • circuits are shown in connection with the switches S and S the details of such circuits do not in 'themselves 'torni part ot the present invention. it Will however be understood that, as previously mentioned, the circuits may give an indication et the condition oit the gear at some remote point or may be circuits used for synchronising or like purposes. Y
  • auxiliary shaft L9 Upon this auxiliary shaft L9 are loosely mounted two bushes or sleeves T and T encircled by a coiled spring U one end of which secured to the upper sleeve T and the other to the lower sleeve T.
  • the sleeve T has a projection T2 engaging with one side of a rib L1" on the arm L9, and the other sleeve T has a projection T3 en- Yith the other side ot the rib.
  • the auxiliary shaft L9 is provided with two pins enga-ging respectively with projecting faces on the sleeves or their flanges. One of these pins T'L is shown in ' Figures '7 and 8 and the other pin T5 is shown in dotted lines in Figure 7.
  • auxiliary shaft L9 The control of the auxiliary shaft L9 is ciieeted by a spring t acting in a manner substantially the same that in which the spring R ot' Figures l, 2 and 3 operates.
  • This spring E upon a lug R4 on a collar R9 secured to t-he auxiliary shaft L9.
  • the construction may be modified to suit switch gear in which it is required that when desired both plugs can be insorted at the same time.
  • a modilication oit this kind may be made in the constructions described by making slots instead of the holes L2 L3 in the locking shaft and by so disposing those holes relatively tothe shaft and the plug sockets H and .l that at one position both plugs can be inserted whilst at other positions one or the other plug only can be'inserted or neither plug can be inserted.
  • the indicator will be arranged. to give the appropriate indication and the auxiliary switches likewise arranged to suit the various positions of the setting lever.
  • the switches are preferably mounted on the fixed or busbar portion of the gear, it is not necessarily so and they may be mounted on the movable portion and be directly operated by the mechanism controlling the position of the locking shaft. In that case however the auxiliary circuits are preferably arranged. so that they are only completed when the movable portion of the gear is racked in.
  • Vhat I claim as my invention and desire to secure by Letters Patent is 1.
  • a plurality of busbar sockets a main switch, sockets connected to said main switch, a movable member having holes or slots at 'levels corresponding to the centre line ot the sockets, a removable plug serving when inserted in one of the main switch sockets to connect it l with one ot the busbar sockets, a pin or projection on said removable plug adapted to enter the corresponding hole in said movable member and means for moving said member to allow the entrance of said pin or projection into the hole and for indicating the selected position of the plug.
  • electric switch gear ot the drawout type the combination of a plurality of busbar sockets, a main switch, sockets connected to said main switch, a tubular member connecting said main switch sockets, a shaft rotatable in said tubular member and provided with holes or slots at levels corresponding to the centre lines ot' the sockets, a removable plug serving when inserted in one oi' the main switch sockets to connect it with one of the busbar sockets, a pin or projection on said removable plug adapted to enter the corresponding hole in the shaft and means for partially rotating the shaft and for indicating the selected position of the plug.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Taps Or Cocks (AREA)
  • Details Of Connecting Devices For Male And Female Coupling (AREA)

Description

Dec. 15, 1925.
J. MIRREY ELECTRIC SWITCH GEAR 4 Sheets-Sheet 1l Filed Dev. 1. 1924 Hmmm MNM Dec; 15, 1925. 1.565.281
J. MIRREY ELECTRIC SWITCH GEAR Filed Dec. l. 1924 4 Sheets-Sheet 2 Dec. l5, 1925 1,565,287
J. MIRREY ELECTRIC SWITCH GEAR Filed Dec. 1, 1924 4 Sheets-Sheet.4 3
mr, draf uw. 1s, 1925. 1,565,287
J. MIRREY ELECTRIC SWITCH GEAR Filed Dec. l. 1924 4 Sheets-Sheet 4 Patented Dec. 1,5, 1925.
UNITED STATES PATENT oFFicr.
JAMES MIRREY, 0F EAST BOLDON, ENGLAND, ASSIGNOR T0 A. REYROLLE & COMPANY, LIMITED, OF HEBBURN-ON-TYNE, ENGLAND, A BRITISH COMPANY.
ELECTRIC SWITCH GEAR.
Application filed December 1, 1924. Serial No. 753,375.
T 0 all 107mm it may concern.'
Be it known that I, JAMES MIRREY, subject of the King ot England, and residing at East Boldon, in the county of Durham, England, have invented certain new and useful Improvements in Electric Switch Gears, of which the following is a specification.
This invention relates to electric switchgear and has particular reference to switchgear used in connection with duplex busbar systems.
In such switchgear the oil-break or other switches are often arranged so that they can be `racked or otherwise moved in and out in relation to the stationary part of the gear containing the busbars and removable plugs are provided serving when in position to some cases mechanism has been provided whereby the insertion of the plug has 0pcrated an indicator and prevented the insertion of the plug for the other busbar.
In switchgear according to the present invention, instead of the indicating mechanism being operated by the insertion of the plug, means are provided whereby the mechanism can be set to indicate a selected position of the plug and also to prevent the insertion of the plug in any other than such selected and indicated position. The insertion of the plug in the proper position locks the indicating mechanism and its setting level' or other operating mechanism.
The setting lever and indicating and locking mechanism are on the movable or drawout portion of the switchgear and preferably there is provided on the xed or busbar portion one or more switches controlling auxiliary circuits, such switches being operated by the setting lever in accordance with its position when the movable portion of the gear is moved in or out. For instance there may be two such auxiliary circuits and switches, one for synchronizing or like purpose and the other :tor giving a remote indication of the position of the plug say by means of a lamp, semaphore or other signal. Conveniently the setting lever is connected to the indicating and locking mechanism through a spring or like yielding coupling interposed at some suitable place to prevent the possibility of damage through rough handling.
Figure 7 is a vertical section of the setting and indicating mechanism of Figure 6 drawn to a larger scale, and
Figure 8 is a cross-sectional plan on the line 8 8 of Figure 7 drawn to a larger scale than that figure.
For convenience Figure 6 will iirst be refered to as illustrating a known type of switchgear to which the invention is applied. In this figure A is a portion of the fixed part of the gear and comprises socket connections at B and C to duplicate busbars and another socket connection at D say to a feeder. The movable or draw-out portion indicated as a whole by the letter E comprises a main oil-break switch in its tank F, a plug connection G cooperating with the socket connection D and socket connections H and J which, by means of a removable plug K can be made to cooperate with either of the busbar socket connections B or C. These parts are well known in themselves and it will be understood that the movable portion E can be racked in and out and that the position of the removable plug K determines which of the busbars is selected for service and joined to the main switch.
Further description of the parts of F igure 6 to which the present invention more particularly relates are given later on and reference is now made to the diagrammatic Figures l to 5.
In Figure l the two busbar sockets B and C, the two sockets H and J of the movable portion and the removable plug K correspond to the parts bearing similar letters in Figure 6.
The usual connection L between the two sockets H and J is made tubular and contains within it a rotatable metal shaft having transverse holes L2 and L3 formed in it at levels corresponding to the centre lines of the sockets H and J. The holes are at an angle so that when one (L2) is in line with its socket H the other (L3) is not in line With its socket J. The removable plug K is formed with a pin or projection K which can enter the hole in the locking shaft L when such hole is in alignment With the socket. Thus the plug K can only loe inserted properly into the socket H or the socket J when the shaft L is turned into the correct position. In the position shown in Figure l the shaft has been turned into such a position thatthe pin K can enter the hole L2 and the removable plug K is fully home in the socket H so that when the movable portion of the switchgear is racked in, connection Will be made to the busbar socket B. i.
The shaft L is provided with an eX- tension L4 preferably of insulating material, upon which is mounted an arm or bracket L5 carrying an arc-shaped indicating plate M Working in conjunction With a Window or opening Mv through which the indications on the plate M can be read. At the top of the shaft L Ll ismounted a bell crank lever N one end ot which is pivoted to a handle or operating lever 0 and the other end pivoted to a link O parallel to the operating lever O and joined to it by another bell crank lever N so that the levei (l moves parallel to thelink O. Stops l) and P provided to limit the movement ot the operating lever O in each direction and round the upper part olf the shaft L LI is a coiled spring R which tends to rotate the shaft into the position shown in Figures 2 and i Where the indicating plate M occupies a central position in. relation to the window M and the shatt L is in such a position that the removable plug cannot be inserted in either of' the sockets H or J.
It will be seen that the ends out the springs R act upon a iixed block R and upon an arm or projection R2' iixed to the shaft and that in the position shown in Figure l the shalft has been rotated into one ei;- treme position of the operating rod O, where7 as previously mentioned, the hole L2 in the sha-'it will allow the entrance of the pin l on the removable plug l. ln this position the indicating plate M would display through the window M the Words Top plug in7 or some equivalent description of the position of the removable plug.
Supposing the gear to be in this position and the movable portion to be racked in, the operating bar O Will depress the handle S of a switch or switches S and cause them to close the circuit or circuits which they control. Sin'iiiarly it the shaft L It be rotated so that the operating lever O lies against the stop P the position ot the parts Will be as shown in Figures 3 and the pin K ot the removable plug ifi being allowed to enter the hole L and the indicator M displaying through the Window M the words Bottom plug in. lli' ,ien the mechanism is in this position the racking in oit' the movable portion of the sivitchgear will cause the operating lever O to depress the handle S2 of the switch or switches S3 and the circuits controlled by those switches will be closed. t Will be seen that the handles S S2' are spring-controlled so that the switch opens when the operating bar no longer depresses the handle. Further the arrangement is such that atte' the bar O has depressed the handle S or S2 it can slide over it keeping it down but putting no l'urther strain on the closed switch.
The removal of the plug K aiter the movable portion of the switch has been racked out will release the locking shaft L and that member Will be turned by the tion of the spring R into the position shown in Figure 4 where neither of the holes L2' or L3 are in alignment With their sockets and consequently the plug K cannot be inserted in either the socket H or the socket J. The indicating plate M will in such circumstances be in its mid position as shown in Figure 2 and Will display the Words ilo plug in or their equivalent. The operating bar O will also be in its mid position Where, it the movable portion of the gear were ra ked in, it would pass between the switch handles S and S2 and not operate either ot them. Obviously a third switch could be provided it' desired to be operated by the bar O when in its mid position.
No circuits are shown in connection with the switches S and S the details of such circuits do not in 'themselves 'torni part ot the present invention. it Will however be understood that, as previously mentioned, the circuits may give an indication et the condition oit the gear at some remote point or may be circuits used for synchronising or like purposes. Y
The details ol" construction in Figures l to 5 are more or less (l ran'iniatic in order to make the operation ot' the invention clear. Such details are in sonic instances varied in the construction shown in Figure (i but where the parts are identical or similar they bear the same rrr/terence letters in Figure o as in Figure l.
Certain modiiicatioi'is ot' construction are embodied in the iorm of switchgear shown in Figure 6 and these will now be described with particular reference to that ligure and to Figures 7 and 8, in which latter iigures they are drawn to larger scales. i
It is preferred to provide a spring or like yielding connection between the operating or setting lever C and the locking shaft L L4 and this detail is shown. in the sec-` llO tional view :forming Figure and in the plan view forming Figure 8. ln these iig-` ures the shaft L4 terminates in a sleeve LG Vto which it is secured by a pin L7. This sleeve L" has secured to it an arm LS carrying the indicator plate M2. Into a guide socket in this sleeve LG the lower end of an auxiliary shaft L9 tits loosely the upper end of this shatt L9 being mechanically connected to the operating bar or setting lever O. Upon this auxiliary shaft L9 are loosely mounted two bushes or sleeves T and T encircled by a coiled spring U one end of which secured to the upper sleeve T and the other to the lower sleeve T. The sleeve T has a projection T2 engaging with one side of a rib L1" on the arm L9, and the other sleeve T has a projection T3 en- Yith the other side ot the rib. The auxiliary shaft L9 is provided with two pins enga-ging respectively with projecting faces on the sleeves or their flanges. One of these pins T'L is shown in 'Figures '7 and 8 and the other pin T5 is shown in dotted lines in Figure 7. The whole arrangement is such that partial rotary movement of the auxiliary shalt L9 by the operating lever O will be transmitted through the spring U to the indicatorM2 and to the locking shatt L L4. The presence ot' the spring U however prevents damage to the gear il an attempt should be made to movcthe setting lever whilst the shat't L is locked by the pin K of the removable plug K.
The control of the auxiliary shaft L9 is ciieeted by a spring t acting in a manner substantially the same that in which the spring R ot' Figures l, 2 and 3 operates. This spring E upon a lug R4 on a collar R9 secured to t-he auxiliary shaft L9.
The above described constructions are `given by way oi example only and varia tions in details may be made without de parting from the spirit oit the invention. For instance the movement ot the locking shait't L although conveniently rotary need not necessarily be such. Any other movenient having` the etlect of setting the indicator and bringing` the holes for the pin l on the removable plug- K into and out oit registration with the sockets may be used.
urther althmigh it is convenient to make the movement of the lever a parallel motion such is not necessarily the case so long the end of the lever is moved so that it can conveniently operate the switches in its various positions'.
Again the construction may be modified to suit switch gear in which it is required that when desired both plugs can be insorted at the same time. A modilication oit this kind may be made in the constructions described by making slots instead of the holes L2 L3 in the locking shaft and by so disposing those holes relatively tothe shaft and the plug sockets H and .l that at one position both plugs can be inserted whilst at other positions one or the other plug only can be'inserted or neither plug can be inserted. In such a case the indicator will be arranged. to give the appropriate indication and the auxiliary switches likewise arranged to suit the various positions of the setting lever. 9
Although the switches are preferably mounted on the fixed or busbar portion of the gear, it is not necessarily so and they may be mounted on the movable portion and be directly operated by the mechanism controlling the position of the locking shaft. In that case however the auxiliary circuits are preferably arranged. so that they are only completed when the movable portion of the gear is racked in.
Although in the above description only two busbars havebeen referred to it willV be understood that the invention may be applied say to a three-phase duplex busbar system and that the setting and indicating mechanism described may be provided for each phase, the setting levers being linked together if desired.
Vhat I claim as my invention and desire to secure by Letters Patent is 1. In electric switchgear of the drawout type, the combination of a plurality of busbar sockets, a main switch, sockets connected to said main switch, a movable member having holes or slots at 'levels corresponding to the centre line ot the sockets, a removable plug serving when inserted in one of the main switch sockets to connect it l with one ot the busbar sockets, a pin or projection on said removable plug adapted to enter the corresponding hole in said movable member and means for moving said member to allow the entrance of said pin or projection into the hole and for indicating the selected position of the plug.
2. ln electric switch gear ot the drawout type the combination of a plurality of busbar sockets, a main switch, sockets connected to said main switch, a tubular member connecting said main switch sockets, a shaft rotatable in said tubular member and provided with holes or slots at levels corresponding to the centre lines ot' the sockets, a removable plug serving when inserted in one oi' the main switch sockets to connect it with one of the busbar sockets, a pin or projection on said removable plug adapted to enter the corresponding hole in the shaft and means for partially rotating the shaft and for indicating the selected position of the plug.
3. In electric switchgear of the draw-out type the combination of a plurality of busbar sockets, a main switch, sockets connected to said main switch, a removable plug serving to connect a selected busbar socket to a main switch socket, mechanism which can be set to indicate the selected position of the plug and to prevent the insertion of the plug in any other than such position and auxiliary switches operated according to the position of said setting mechanism.
4. In electric switchgear of the draw-out type the combination of a plurality of busbar sockets, a main switch, sockets connected to said main switch, a tubular member connecting said main switch sockets, a shaft rotatable in said tubular member and provided with holes or slots at levels corresponding to the centre lines of the sockets, a removable plug serving when inserted in one of the main switch sockets to connect it with one of the busbar sockets, a pin or projection on said removable plug adapted to enter the corresponding hole in the shaft, a lever for partially .rotating said shaft and auxiliary switches operated according to the position of said lever.
5. In electric switchgear of the draw-out type the combination of a plurality of busbar sockets, a main switch, sockets connected to said main switch, a tubular member connecting said main switch sockets, a shaft rotatable in said tubular member and provided with holes or slots at levels corresponding to the centre lines of the sockets, a removable plug serving when inserted in one of the main switch sockets to connect it with one of the busbar sockets, a pin or projection on said removable plug adapted to enter the corresponding hole in the shaft, a lever for partially rotating said shaft and a yielding coupling or connection between the lever and the shaft.
6. In electric switchgear of the draw-out type the combination of a plurality of busbar sockets, a main switch, sockets connected to said main switch, a tubular member connecting said main switch sockets, a shaft rotatable in said tubular member and profvided with holes or slots at levels corresponding to the centre lines of the sockets, a removable plug serving when inserted in one of the main switch sockets to connect it with one of the busbar sockets, a pin or projection on said removable plug adapted to enter the corresponding hole in the shaft, a lever for partially rotating said shaft, a yielding coupling or connection between the lever and the shaft and auxiliary switches operated according to the position of said lever.
7. In electric switch gear of the draw-out type, the combination of a plurality of bus bar sockets, a main switch, sockets connected to said main switch, a movablel member having an opening for each socket, but one of which may register with a socket at a time, a removable plug serving when inserted in one of the main switch sockets to connect it with one of the bus bar sockets, a projection on said removable plug adapted to enter an opening in said movable member and means for moving said member to allow the entrance of said projection in any selected hole.
In testimony whereof I have signed my name to this specification.
JAMES MIRREY.
US753375A 1924-01-14 1924-12-01 Electric switch gear Expired - Lifetime US1565287A (en)

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GB1018/24A GB231947A (en) 1924-01-14 1924-01-14 Improvements in or relating to electric switchgear

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE767787C (en) * 1936-06-23 1953-06-08 Siemens Schuckertwerke A G Oil protection for encapsulated low-voltage switchgear in a capsule housing designed to allow the oil protection to be extended and retracted in a straight line
US10320161B2 (en) * 2015-07-13 2019-06-11 Abb Schweiz Ag Mechanical rack position indicator

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE767787C (en) * 1936-06-23 1953-06-08 Siemens Schuckertwerke A G Oil protection for encapsulated low-voltage switchgear in a capsule housing designed to allow the oil protection to be extended and retracted in a straight line
US10320161B2 (en) * 2015-07-13 2019-06-11 Abb Schweiz Ag Mechanical rack position indicator

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Publication number Publication date
GB231947A (en) 1925-04-14
FR591873A (en) 1925-07-20

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