US1195790A - Island - Google Patents

Description

L. W. DOWNES & A. W. FAXON.

0H. FUSE.

APPLICATION FILED IIAY 27.19141 7 9w m \NI 3 v 1 m8 W M m S v m 1 ma w a P IQ Q? an.

L. WLDOWNES & A. W. FAXON.

OIL FUSE.

APPLICATION FILED MAYZT. 1914.

Patented Aug. 22, 1916.

I 3 SHEETS-SHEET 2- after/"44 a W v 1 M Mn 7 wmy. 1 wfw L. W. DOWNES & A. W. FAXON.

OIL FUSE.

APPLICATION FILED MAY 27. 1914.

3 SHEETSSHEET 3.

Patented Aug. 22, 1916.

LOUIS W. DOWNES AND ALFRED w.

raxon assmnon ,'.l0 n a w roar. RATION or BHODE ISLAN I1 13101:, or rnovrnmzcz, anon: Isnnzn; sam co., or-rnovmmrcn, BHODE lsnmn, a conro- OIL-FUSE.

I Specification of Letters mum. I P t t 1 Application a ea Iay 21, 1014. Serial nd-ggarass.

To all whom it may concern:

Be it known that we, LOUIS W. Do'wNEs and ALFRED W. FAXON, both citizens of the United States of America, and residents of Providence, Rhode Island, have invented a new and useful Im rovement in Oil-Fuses, which invention is ullyset forth in the following specification.

The present invention relates to oil fuses, especially of the type disclosed in our pending application for U. S. Patent Serial No. 710,044, filed July 17, 1912, and renewed February 26, 1914, Serial No. 821,318. The inclosing casing of the structure of that application comprises a cup-like receptacle or lower part and a detachable ring or upper part over the upper open end of the lower part, with a removable cover closing the central opening in said upper part. In that structure the main circuit terminals are attached to the cup-like receptacle or lower part through the intermediary of suitable blocks of insulation, and the receptacle was providedwith means for fastening it to a building, wall, pole or other support. According to our present invention, we propose to enlarge the upper part and make it what might be regarded as the main part of the casing, to be fastened to a building, wall, pole or other support. A cover (as before) closes an opening at the top of said upper casing-part, and the bottom or cup-like receptacle depends below and is detachably joined to said upper part. We mount the fixed main circuit terminals upon suitable insulation supported from the upper casingpart (instead of the receptacle or lower part) with the line conductors or cables also entering through the wall of said upper casing-part; the fuse-carrier is loosely or'movably supported from the cover, whereby it becomes self-alinable in the engagement of its fuse-terminals with the fixed main circuit terminals; and we provide special means in conjunction with the gas vent opening or openings to prevent the escape of oil therethrough upon blowing of a fuse. The many advantages of these and other features of the present invention may be readily understood and most conveniently described by reference to the accompanying drawings, in which Figure 1 is a vertical sectional view on line 11 of Fig. 2, with parts in elevation; Fig. 2 is a top plan view, with parts in section, on line 2 -2 of Fig. 1; Fig. 3 is a vertical section on line 3-3 of Fig. 2 with parts in eleyation; Fig. 4 is a detail view of the insulatmg frame or base upon which the main circult terminals are mounted; Fig. 5 is a top plan new of the lower part or receptacle of the casing; Fig. 6 is a detail perspective view'of the fuse carrier; Fig. 7 is a detail sectional view on line 77 of Fig. 1; Figs. 8 and 9 are detail views of terminals; Figs. 10 and 11 are vertical sectional views, on planes at right angles to each other with parts m elevation, showing the cover of the casing with a modified structure of fusecarrier and parts mounted thereon; and Flgs. 12 and 13 are detail views of parts shown in Figs. 10 and 11.

2Q is the upper dome-like part of the inclosmg casing, having a large circular openmg 21 at its under side and at its top a smaller circular opening 22 closed by a cap 65 described later. Notched arms 23, 23 on the casing-part 20 serve to secure the structure to a building, wall, pole or other support. Terminal conductors or cables 24, 25 enter the casing-part 20 at opposite sides, each conductor passing upward through a bushing 26 held in place by a screw 27. About each bushing 26 there is a groove in which there is wound a soft cord 28 constituting a packing makin an oil-tight joint between the bushing an wall of the opening. The openings on the under side of the casing-part 20 in which the bushings 26 fit are enlarged about the upper ends of the bushings to receive a fillin of a suitable oilproof cement 29 (such as s iellac-gum poured in While liquid) which seals the cable entrances and presents oil-tight joints at these points.

30 is an approximately rectangular-shaped open centered frame, support or screen made of suitable insulatin material, preferably such as that commercially known as molded insulation, composed of a fibrous base of ingredients such as ground asbestos or other powdered substances, and a binding compound such as rubber or bakelite. Four upwardly projecting posts 31 on the frame 30 bear against the lower ends of four fingers or studs 32 depending from the top wall of the casing-part 20 (preferably cast integrally therewith) around the top opening 22. Four screws 33 pass upward through posts 31, respectively, and into screwthreaded engagement with openings in the lower end of fingers 32, thereby rigidly securing the insulating frame 30 to the casingpart 20 in a suspended position. Two 1nside opposing flanges 34, 34 of the frame 30 each have two vertical perforations.

35 is a spring-brush terminal riveted to the depending arm 36 of a plate 37 which bears upon the top of the ledge formed by one of the flanges 34. A metal striplor plate 38 fits against the plate 37 and anot er metal strip or plate 39 fits against the bottom face of the flange or ledge 34. A screw 40 passes downward through the plates. 38 and 39, through one of the perforations in the fia'n'ge 34, and into screw-threaded engagement with plate 39. Another screw 41 passes up ward through plate 39., the other perforation in flange 34, through plate 37, through plate 38 in screw-threaded engagement therewith, through a small nut 42, and then into an elongated nut 43. The insulation is removed from the inner end of the conductor 24 and the exposed end 44 of the copper wire is soldered or sweated into the upper end of the nut 43, as most clearly illustrated in Fig. 7. A serving 45, of linen thread for example, is wrapped about the insulation on the conductor 24 adjacent its exposed end 44, and a wrapping of tape 46 (varnished cambric tape, for example) covers the joint between the nut 43 and conductor 24. Duplicates of these partsterminal brush 35, plates 37, 38, 39, screws 40, 41, nuts 42, 43, serving 45, and tape wrapping 46are associated with the other flange or ledge 34 of the supporting frame 30 and the inner end of conductor 25.

It is most important to get the fixed termicenter; and working from this opening 22 and its machined surface, the location of the insulating frame or support 30 is accurately determined in securing that frame in position by means of the four screws 33. This may occasion removal of portions of the upper end of one or more of the posts 31, or the interposition of suitable packing-washers (not shown) between the opposing ends of one or more pairs of the posts 31 and fingers 32. The fixing of the insulating frame 30 to or suspending it from the upper casingpart 20 (instead of mounting it in the lower receptacle portion of the casing. as in the structure shown in our patent application before mentioned) also greatly facilitates the assembling of the complete structure, inasmuch as said frame 30 and parts associated therewith are easily accessible from the under side of the casing-part 20 with the 50 is the lower part of the inclosing cas-,

ing in the form of a cup-like receptacle having three depending legs 51 upon whlch the device may stand in an upright position when not attached to a support by means of the-arms 23 before mentioned. A drain opening through the bottom of the receptacle 50 is closed by a tapered screw-plug 52; on the surface of the bottom, short ribs 53 radiate about the opening. An insulating lining 54 of suitable material, such as whalebone, paper or other insulating fibrous combination, fits closely within the receptacle 50 and rests against the ribs 53. Perforations 55 through the bottom of the lining permit the arc-suppressing liquid or oil to drain through the lining along the bottom surface of the receptacle 50 between the ribs 53 tothe drain outlet. A washer 56 of insulating material, similar to that of the lining, fits against the bottom surface of the receptacle 50under the perforations 55 and about the ribs 53, as clearly shown in Figs. 1 and 3, thereby preventing short circuiting or arcing through the perforations 55 to the metal wall of the receptacle 50. The upper circular edge 57 of the receptacle 59 makes a tight joint against a gasket 58 seated in a groove around the circular opening 21 in the under side of the casing-part 20. Four bolts 59 pass through the arms 23, 23 and ears 60,, 60 (Fig. 2) of theupper casingpart 20, and through four lugs 61, respectively, about the upper edge of the receptacle part 50, thus securely fixing the latter to the upper casing-part 20. I

The circular opening 22 through the top of the casing-part 20 is-c'losed by a cover having a hollow plug-like part 66 fitting closely within said circular opening, and a depending hood-like flange 67 forming an annular groove or recess to receive a packing gasket 68. An upwardly projecting flange 69 on the casing-part 20 around the opening 22 telescopes within the flange 67 and seats against the gasket 68. Vertical grooves 70 and 71 are cut in the wall of the circular opening 22, the groove 71 being slightly wider than the groove 70. Studs or stops 72 and 73 (Fig. 1 and dotted lines Fig. 2) depend from the upper Wall of the casingpart 20 adjacent the circular opening 22. Two lugs 74 and 75 (Fig. 3 and dotted lines Fig. 2) project outwardly at the lower end of plug-like part 66 of the cover 65, the lug 74 being slightly wider than the lug 75. In applying the cover to the casingpart 20, the lug 75 passes downward through the groove 70 and the wider lug 74 downward through the wider groove 71, and the cover is then rotated in the direction of the arrow (Fig. 2) to carry the lugs under the overhanging edge about the opening 22. A bayonet 'joint is thus provided for locking the cover in place. The making of the grooves and the lugs of difl'erentwidths requires that the parts always be brought to the same definite position before the cover can be put in place and locked. The stud 73 stands in the path of the lug 74, preventing rotation of the cover in a direction op- 1 posite that of the arrow (Fig. 2). The stud 2 standing in the path of the lug 74 limits rotation of the cover through an arc of 90 to the position shown in Fig. 2 and carries a pointer lug 76 on the outer edge of flange 67 to a position opposite a word Lock, (see Fig. 2) formed on the casing-part 20 in any suitable way, preferably in the casting thereof. Rotation of the cover in the reverse direction of the arrow Fig. 2 brings the lugs and grooves of the bayonet joint into register for removal of the cover and the pointer 76 opposite the word Unlock, also formed upon the casing-part 20 in any suitable way, preferably in the casting thereof.

The disruption of a fuse-link by an excessive current is accompanied by the instantaneous formation of pressure-generating gases; and if such action takes place within an inclosing casing, adequate vent must be provided for the ready escape of such gases and consequent relief of internal pressure. This applies particularly to fuse structures adapted to handle large currents; it being impracticable to make the inclosing casing of such strength as to withstand the internal pressure, it would explode with great danger and destruction unless adequate vent be provided. Much difiiculty has been experienced in oil-fuse structures in providing one or more vents of adequate area while at the same time avoiding escape or leakage of oil through such vents to the exterior of the structure upon disruption of the fuse. Such escape or discharge of oil presents several very serious objections, among which are the following: The oil level in the inclosing casing may lower to such point as to prevent the oil or arc-suppressing liquid affording the certainty of safety in operation intended by its presence. Leakage or dripping of oil from the exterior of the structure might seriously damage neighboring property; for example, if-the structure were mounted on a pole, the oil might drip upon the clothing of a passerby, resulting in damage claims which might be a source of very considerable loss and annoyance to public service corporations using oil-fuse structures in their equipments. By the structure disclosed in this application and about to be described, we have provided one or more vents of ample capacity, while at the same time of such construction as to avoid any blowing out or leakage of oil to the exterior of the device upon blowing or disruption of the fuse.

The cover 65, preferably a hollow casting of the peculiar form shown, is made with two chambers 77 and 78, the lower chamber 77 opening into the interior of the casing when the cover is. in lace. Chamber 77 is in communication wit chamber 78 through one or more passages 79 (two being used in the structure illustrated), each fitted at its upper end with a tube 80, preferably of brass, extending upward within the chamber 78 and terminating beneath a semispherical portion 81 of the under surface of a cap 82 detachably fastened to the cover by two screws 83 (Figs. 1 and 3). Cap 82 has a short flange 84 depending within the cover outside of the upper ends of the brass tubes 80, and a long flange 87 depending around the upper end of cover 65. Fine wire gauze 85, either in the form of disks, cups or spiral, is inserted within the brass tubes 80. One or more small drain openings 86 through the wall of each tube 80 fust above the bottom of chamber 78 drain any oil that may collect in the bottom of said chamber back through the passages 79 and through chamber 77 into the main casing. We have discovered that, by properly proportioning the area of these small drain holes 86, oil will thus drain back very readily, but any water which might, from unknown cause, collect in chamber 78 cannot pass through these openings, owing to the fact that the weight of the water is not suflicient to overcome the surface tension of ihe film of oil which effectually closes the ole.

The operation of the venting means described is simple. When the fuse-link in the main casing is disrupted or blown by excessive current, gas and oil commingled in a finely divided condition are forced upward through chamber 77 passages 79, and into contact with the gauze 85 in the tubes 80. The gauze acts to arrest the particles of oil, though permitting the gas to pass on upward and out of the structure along the path of the arrows, top of Fig. 1. Such small particles of oil as may, in extreme cases, be carried on upward and out of the upper end of the wire-gauze 85 and tubes 80 will strike the semi spherical surface 81 and drain to the bottom of chamber 78 and thence through openings 86 back to the main casing.

90 is a fuse-carrier having having a cylindrical middle portion, a reduced upper I end 91 with flattened opposite sides, and a flattened lower end 92 with concave faces. The part 92 constitutes an insulating partition or barrier isolating the terminals positioned on opposite sides thereof, as presently explained. The fuse carrier may be made of. any suitable insulating material, but we prefer hard wood, such as birch, impregnated (in vacuum) with a suitable oil, such for example as the well-known transformer oil. A pivot pin 94, engaging openings in lugs 74 and 75 and passing'loosely through a horizontal opening 95 of larger diameter through the reduced upper end 91 of thefuse-carrier, loosely suspends the fuse-carrier 90 from the cover 65. The end 91 of the fuse-carrier projects into the chamber 77 (see Figs. 1 and 3) and bears loosely against a boss96 centrally depending from site sides of the lower end 92 of said car- 7 rier. Each terminal 124 is secured in place by two screws 125, 125, and its outer surface is curved at 126 to make rotatable engagement with.- a circuit terminal brush 35. A screw 127 passes through the lower end of terminal 124- and carries a clamping nut 128 positioned on the inner end thereof between the depending arm of the terminal and the opposing face of the fuse-carrier 90. A fuse-link extending around and across the lower end of the fuse-carrier is composed of two end sections 99, 99 notched or hooked (as shown in dotted lines Fig. 3) for engagement with screws 127, 127, and a connecting middle section 100 which may overlap and be soldered to the end sections, as illustrated in Fig. 1. The end sections 99, 99 may be of copper and the middle section 100 of a suitable low meltingalloy, the melting point of which is preferably below the carbonizing point'of the arc suppressing o1 r Figs. 10 to 13 of the drawings illustrate a type of construction designed especially for use with currents of exceptionally high voltages, such as 6,600, 11,000 or 13,000 volts, but also capable of working equally well with currents of lower voltage. Except as to matters specifically described, this construction is substantially the same as that" illustrated in Figs. 1 to 9 and hereinbefore described. With the object of securing a longer break between the fuse terminals on the blowing of the fuse, the two and sections of the fuse-link are connected to two spring rollers, respectively, of the rollerlow melting alloy.

curtain type. Upon disruption or melting of the fuse-link at its middle, these rollers immediately operate to wind up the discon- .carrier 105 has a lower end partition or barrier 106 with approximately plane faces on opposite sides. The two fuse terminals each consists of an angle plate secured inplace by two screws 116, 116, engaging a horizontal part 107 of the plate. A vertically depending part 108 of the plate serves to make engagement with one of the circuit terminals (such as 35, Fig. 1) within the inclosing casing of the device. A roller 109 is positioned between two depending arms 111, 111 of plate 107 and journaled on an axle 110 supported by said arms.

The roller or drum 109 is preferably formed in two cup-like castings fastened together by four rivets 112, Fig. 12. A projection 113' on each casting is adapted to project into the path of the arms 111 to limit the rotation of the drum, as presently explained. The drum-actuating spring 119, entirely inclosed by the drum, is anchored at one end to the axle 110 and at its other end fastened to the peripheral wall of the drum by a rivet 114; it constantly tends to sections or hands 120, 120, preferably of hard rolled copper, each band being at one end carried around and fastened to the peripheral surface of its drum by a rivet 115. At its other end, each band carries a screwbolt clamp 117 for making connection to one end of the intermediate fusible section or element 118 which may be of any suitable With the parts of the fuse-link assembled and in the position of the fuse-carrier best shown in Figs. 10 and 12, the intermediate fusibl strip or element 118 stretches across the grooved lower edge of the insulating barrier or partition 106 of the fuse-carrier, its hook-formed ends engaging the shanks of screws 117, 117 outside of the lower extremities of bands 120, the overlapping ends of the bands and strips being clamped between the heads of the screws 117 and the nuts thereon. At their inner extremities the screws 117 bear against the opposite faces of the .part 106 of the carrier, holding thecopper strips 120, 120

and a lower receptacle part detachably joined,

to the upper part; circuit-terminals within said casing supported from the upper part thereof; a fuse carrier supported within the casing from the upper part thereof and independent of the lower receptacle part, said carrier having terminals adapted for engagement wth the circuit-terminals; and a fuse-link connected between said fuse-terminals.

2. In an electric fuse structure, the combination of a casing including an upper art and a lower receptacle part detachably joined to the upper part; circuit-terminals within said casing supported from the upper part thereof; a fuse carrier supported within the casing from the upper part thereof and independent of the lower receptacle part, said carrier having terminals adapted for engagement with the circuit-terminals; a fuselink connected between said fuse-terminals and an arc-suppressing liquid in said casing in contact with the fuse-link.

3. In an electric fuse structure, the combination of a casing including an upper part, a lower receptacle part detachably joined to the upper part, and a cover closing a top opening in the upper part; circuit-terminals within said casing supported from the upper part thereof; a fuse carrier within the casing removable therefrom through the opening closed by the cover and having terminals adapted for engagement with the circuit terminals; and a fuse-link connected between said fuse-terminals.

4. In an electric fuse structure, the combination of a casing including an upper part and a lower receptacle part detachably joined to the upper part; circuit-terminals within said casing supported from the upper part thereof; line conductors associated with the upper casing part and joined to the circuit terminals; a fuse carrier supported within the casing from the upper part thereof and independent of the lower receptacle part, said carrier'having terminals adapted for engagement with the circuit-terminals; and a fuse-link connected between said fuse-terminals.

5. In an electric fuse structure, the combination of a casing including an upper part and a lower receptacle part detachably joined to the upper part; circuit-terminals within said casing supported from the upper part thereof; line conductors entering through the wall of the upper casing part and joined to the circuit terminals; a fuse-carrier supported within the casing from the upper part thereof and independent of the lower receptacle part, said carrier having terminals adapted for engagement with the circuit-terminals; and a fuse-link connected between said fuse-terminals.

6. In an electric fuse structure, the combination of a casing including an upper domelike part, a lower cup-like receptacle part detachably fixed to and closing the under open side of said upper part, and a removable cover closing a top opening in the upper casing part; circuit-terminals within said casing supported from the upper part thereof; a fuse carrier within the casing supported from and removable with the cover;

and a fuse-link connected between said fusete'rminals.

7. In an electric fuse structure, the combination of an inclosing casing including an upper part, a lower receptacle part detachably joined to the upper part, and a cover closing the top openmg in the upper part; an opencentered insulating frame supported within the casing from the upper part thereof; circuit-terminals within said insulating frame; a fuse-carrier suspended from the cover and depending within said insulating frame; fuse-terminals on said fuse-carrier adapted for engagement with said circuitterminals; and a fuse-link connected between said fuse-terminals.

8. In an electric fuse structure, the combination of an inclosing casing; circuit terminals within said casing; a fuse-carrier in the casing having thereon fuse-terminals adapted by movement of the carrier to be engaged with and disengaged from the circuit terminals, said carrier being supported within the casing from a part thereof to which it is joined and having a freedom of movement relative to said casing part permitting selfalinement of its fuse terminals with the circuit' terminals in engaging the same with each other; and a fuse-link connected between the fuse-terminals on the carrier.

9. In an electric fuse structure, the combination of an inclosing casing having a removable cover;

circuit-terminals withiii said casing; a fuse carrier in the casing having thereon fuse-terminals adapted by movement of the carrier to be engaged with and disengaged from the circuit-terminals, said carrier bein supported from the casing cover with a freedom of movement relative to and independent of said cover permitting self-alinement of its fuse-terminals with the circuit-terminals in engaging the same with each other; and a fuse-link connected between the fuse-terminals on the carrier. I

10. In an electric fuse structure, the combination of an inclosing casing having a ing thereon fuse-terminals adapted by movement of the carrier to be engaged with and disengaged from the circuit-terminals, said carrier being suspended from the casing cover by a pin on one of said parts loosely engaging an opening in the other, thereby giving a freedom of relative'movement permitting self-alinement of the fuse-terminals with the circuit-terminals when brought into contact with each other; and a fuse-link connected between the fuse-terminals on the carrier.

11. In an electric oil fuse structure, an inclosing casin including a part having a vented cham er communicating with the main chamber of the casingthrough one or more vent passages containing a filling of reticulated materialand an arc-suppressing liquid in said main chamber.

.12. In an electric oil fuse structure, an in.-

closing casing including a part having a vented chamber communicating with the main chamber of the casing through one or more vent passages containing a filling of fine wire gauze and an arc-suppressing liquid in said main chamber.

13. In an electric oil fuse structure, an inclosing casing comprising a main chamber and a small vented chamber with one or more vent passages leading from the main chamber and discharging into the small chamber beneath the top wall thereof, said small, chamber also having one or more liquid return passag s from the bottom thereof back into the main chamber of the casing, and a filling of reticulated material in said vent passage or passages. V

14. In an electric oil fuse structure, a casing having therein a main chamber and a small vented chamber having a top wall with a'dome-like under surface with one or more vent passages leading from the main chamber and discharging into the small chamber beneath a dome-like under surface of the top wall thereof, and a filling of re= ticulated material in said vent passage or;

passages.

15. In an electric oil fuse structure, a casing having therein a main chamber and a small vented chamber with a vent passage leading from the main chamber and discharging into the small chamber, the walls of the small chamber including an upwardly projecting flange, a cap havin a flange depending about the upward y projecting flange, and another flange depending inside of the upwardly projecting flange between the same and the discharge end of the vent passage from the main chamber.

16. In an electric oil fuse structure, an inclosing casing having a main chamber and including a cover having a small vented chamber into which a vent passage leads closing casing having a main chamber and including a cover having therein a small vented chamber closed by a cap on the cover and in communication with the main chamber of the casing through a vent passage the upper end of which terminates near the underside of the cap and an arc-suppressing liquid in the main chamber.

18. In an electric fuse structure, 'a fuselink, and a drum or roller having means adapted to wind up said fuse-link when the same is broken by excessive current and thereby lengthen the break between the severed ends of the link.

19. In an electric fuse structure, a fuselink having a flexible end section, and a drum or roller adapted to automatically wind up said flexible end section when the fuse-link is broken by excessive current.

20. In an electric fuse structure, a fuselink having a flexible end section, and a spring-actuated drum or roller adapted to wind up said flexible end section when the fuse-link is broken by excessive current. 21. In an electric fuse structure, a fuselink having flexible end sections and a. fusible section connected between the same, and

a spring-actuated drum or roller for each end section adapted to wind up thesame when the middle fusible section is broken by excessive current.

22 In an electric fuse structure, a fusecarrler including an msulatmg barrier or partition; a fuse-link extending from one side of said barrier to the other around the edge thereof, said link having flexible end sections and a fusible section connected between the same; and two spring-actuated drums or roller s mounted on the carrier on opposite sides of the insulating partition and adapted to wind up the end sections respectively when the fusible section is broken by excessive current.

23. In an electric fuse structure,the combination of a-casing including an upper part and a lower part detachably oined together; an'open centered insulating frame supported within the casing from the upper part thereof; circuit-terminals mounted within said insulating frame; a fuse-carrier in the easlng projecting into said insulating frame and having fuse-terminals adapted for engagement with the circuit-terminals and isolated from each other by a portion of the carrier constituting an insulating barrier or partition; and a fuse-link connected between said fuse-terminals and extending around the edge of said insulating barrier portion of the fuse-carrier.

24. In an electric fuse structure, the com- 10 moved into and out of engagement with said circuit terminals; and a fuse-link connected between said fuse-terminals.

In testimony whereof we have signed this specification in the presence of two subscribing witnesses.

LOUIS W. DOWNES. ALFRED W. FAXON. Witnesses GEORGE W. S'I'EERE, P. O. BAKER.

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