US2900478A - Circuit interrupter - Google Patents

Circuit interrupter Download PDF

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Publication number
US2900478A
US2900478A US574171A US57417156A US2900478A US 2900478 A US2900478 A US 2900478A US 574171 A US574171 A US 574171A US 57417156 A US57417156 A US 57417156A US 2900478 A US2900478 A US 2900478A
Authority
US
United States
Prior art keywords
contact
arc
closure plate
casing
venting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US574171A
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English (en)
Inventor
Robert E Friedrich
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Westinghouse Electric Corp
Original Assignee
Westinghouse Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Westinghouse Electric Corp filed Critical Westinghouse Electric Corp
Priority to US574171A priority Critical patent/US2900478A/en
Priority to GB8783/57A priority patent/GB806229A/en
Priority to CH351010D priority patent/CH351010A/de
Application granted granted Critical
Publication of US2900478A publication Critical patent/US2900478A/en
Priority to DEP24948A priority patent/DE1149367B/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H5/00—Feeding articles separated from piles; Feeding articles to machines
    • B65H5/30—Opening devices for folded sheets or signatures
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H3/00—Separating articles from piles
    • B65H3/08—Separating articles from piles using pneumatic force
    • B65H3/12—Suction bands, belts, or tables moving relatively to the pile
    • B65H3/124—Suction bands or belts
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/70—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid
    • H01H33/88—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid the flow of arc-extinguishing fluid being produced or increased by movement of pistons or other pressure-producing parts
    • H01H33/90—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid the flow of arc-extinguishing fluid being produced or increased by movement of pistons or other pressure-producing parts this movement being effected by or in conjunction with the contact-operating mechanism
    • H01H33/92—Switches with separate means for directing, obtaining, or increasing flow of arc-extinguishing fluid the flow of arc-extinguishing fluid being produced or increased by movement of pistons or other pressure-producing parts this movement being effected by or in conjunction with the contact-operating mechanism the arc-extinguishing fluid being liquid, e.g. oil
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2301/00—Handling processes for sheets or webs
    • B65H2301/30—Orientation, displacement, position of the handled material
    • B65H2301/32—Orientation of handled material
    • B65H2301/321—Standing on edge
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2301/00—Handling processes for sheets or webs
    • B65H2301/40—Type of handling process
    • B65H2301/43—Gathering; Associating; Assembling
    • B65H2301/435—Gathering; Associating; Assembling on collecting conveyor
    • B65H2301/4351—Gathering; Associating; Assembling on collecting conveyor receiving articles astride thereon

Definitions

  • This invention relates to circuit interrupters in general, and, more particularly, to arc-extinguishing structures therefor.
  • a general object of the invention is to provide an improved circuit interrupter particularly of the liquid-break type, in which the interrupting structure is comparatively simple, and in which the parts are readily accessible for inspection and maintenance.
  • Another object of the invention is to provide an improved arc extinguishing unit in which the several parts are readily assembled and may be quickly disassembled, with means for providing an effective arc-extinguishing action over the entire current range.
  • Another object of the invention is to provide an improved liquid break circuit interrupter having an improved piston construction and mounting therefor, in which ready accessibility may be had, and whereby the piston structure together with the movable contact structure may be easily disassembled from the arc-extinguishing unit, without disturbing the associated grid block or the relatively stationary contact structure.
  • a further object of the invention is to provide an improved arc-extinguishing unit, particularly of the liquidbreak type, in which improved venting means are provided, being valve controlled, and closing during the interruption process.
  • Another object is to provide an improved circuit interrupter of the typeemploying a cylindrical casing with an interrupting grid block supported in diametrically opposed .side openings in the wall of the casing, in which the stationary contact structure may be removed through one of the side openings after removal of the interrupting grid block.
  • Figure 1 is a fragmentary, vertical sectional view through .a tank-type, liquid-break circuit interrupter embodying the invention, and the contact structure being shown in full lines in the closed-circuit position;
  • Fig. 2 is a considerably enlarged, vertical sectional view taken through the left-hand arc-extinguishing unit of Fig. 1, with the contact structure being shown in the closedci-rcuit position;
  • Fig; 3 is a sectional view taken substantially along the line IIIIII of Fig. 2, looking in the direction of the arrows;
  • a Fig. 4 is a fragmentary plan view of a portion of the side wall of the arc-extinguishing unit, showing the associated shunting resistor and one of the clamping plates for maintaining the grid block fixedly in position;
  • Fig; 5 is a fragmentary side elevational view, looking in the direction of .V-V of Fig. 4, with certain portions omitted forclarity;
  • : ⁇ Fig 6 is an' enlarged vertical sectional view taken substantially along ,the line of the grid block illustrated in, F g.5, showing its internal construction;
  • Fig. 7 is a side elevational view of the insulating tubu- 2,900,478 Patented Aug. 18, 1959 lar casing utilized in the construction of the improved arcextinguishing unit with the grid block in place;
  • Fig. 8 shows a vertical sectional view taken through a tubular contact member during an initial step of fabricating the relatively stationar; contact fingers;
  • Fig. 9 is an end elevational view of the contact member of Fig. 8.
  • Fig. 10 illustrates the contact member of Fig. 8 having an annular arc resisting tip member secured therein, with the resulting assembly slotted to form segmental relatively stationary fingers;
  • Fig. 11 is an end elevational view of the resulting contact fingers following the slotting operation
  • Fig. 12 is a side elevational view of the contact mounting stud utilized in the arc-extinguishing unit for supporting the stationary contact fingers;
  • Fig. 13 is an inverted plan view of the pump cylinder utilized in the circuit interrupter.
  • Fig. 14 is a sectional view taken along the line XIVXIV of the pump cylinder of Fig. 13.
  • the reference numeral 1 designates a tank filled to the level 2 with a suitable arc-extinguishing fluid 3, in this particular instance circuit breaker oil.
  • a suitable arc-extinguishing fluid in this particular instance circuit breaker oil.
  • a pair of terminal bushings 4, 5 to the lower ends of which are clamped identical arc-extinguishing units, generally designated by the reference numeral 6, and electrically interconnected in the closed-circuit position, as shown, by a conducting cross-bar 7.
  • the cross-bar, or bridging member 7 is vertically actuated in a reciprocal manner by an insulating lift rod 8, the operation of which may be effected by any suitable operating mechanism, not shown, and specifically forming no part of the invention.
  • a contact foot 9 is threaded and clamped to the lower end of the terminal stud 10, which extends upwardly internally within the terminal bushing 4.
  • the contact foot 9 is bolted by three bolts 11, only one of which is shown in Fig. 2, to an upper closure plate 12 formed of brass or other suitable conducting material.
  • the upper closure plate 12 has a plurality of apertures 13 drilled therethrough in spaced manner about its circumference, through which pass mounting bolts 14, which threadedly secure the closure plate 12 to an insulating tubular casing or shell 15, the latter being shown more in detail in Fig. 7 of the drawings.
  • a plurality of mounting apertures 16 are drilled through the side Wall of the casing 15 near the ends thereof.
  • Barrel nuts 17 (Fig. 2) are inserted within the apertures 16 of the tubular casing 15, and the mounting bolts 14 extend through additional holes 18 drilled longitudinally through the side walls of the casing 15 and terminate in tapped apertures 19 provided in the barrel nuts 17.
  • the tubular casing 15 is securely attached to the upper closure plate 12.
  • the upper closure plate 12 also has a plurality of, in this instance three, tapped apertures 20, within which are threadedly secured valve casings 21 having associated therewith valve discs 22 and compression springs 23, which bias the valves 22 to the open position.
  • This permits venting from the interior 24 of the insulating casing 15, through one or more apertures 25 drilled through the side wall of the valve casing'21 and through the latter to the region externally of arc-extinguishing unit 6.
  • a plurality of normally open valves generally designated by the reference numeral 26,
  • a tubular contact member 36 shown more clearly in Fig. 8, is suitably machined to provide a plurality of spring seats 37 and end bosses 38.
  • Figs. 8 and 9 show the tubular contact member 36 following the machine operations.
  • an annular arc resisting tip member 39 (Fig. is brazed within the tubular member 36.
  • the assembly is slotted, as indicated in Figs. 10 and 11 to form a plurality, in this particular instance six, segmental stationary contact fingers 35.
  • Each contact finger 35 is biased radially inwardly by compression springs 44], which seat at one end within the spring seats 37, and which hear at their outer ends against the inner wall of the contact finger casing 34.
  • Each contact finger 35 has its individual arc-resisting contact portion 39a.
  • the upper ends 41 of the contact fingers 35 bear against a depending stud portion 42 integrally associated with the contact stud member 28.
  • a rod-shaped lower movable contact 43 to the lower end of which is fixedly secured an apertured disc 44, which serves as a spring seat for a compression spring 45.
  • the upper end of the compression spring 45 seats interiorly within a pump cylinder 46, the configuration of which is more readily apparent from an inspection of Figs. 13 and 14 of the drawings.
  • the pump cylinder 46 is in casting form and contains a plurality of, in this instance three, venting passages or channels 47 which lead at their lower end through venting apertures 48, provided in the lower closure plate 49, to the region exteriorly of the arc-extinguishing unit 6.
  • the upper ends of the passages 47, cast within the casting 46 lead into the interior 56 within the pump cylinder 46 through openings 51 (Fig. 14).
  • the pump cylinder 46 has its side walls 52, at the lower ends thereof, removed, as at 53, for a purpose which will be more apparent hereinafter.
  • tapped apertures 54 are provided at the lower end of the pump cylinder 46. These tapped apertures 54 are to accommodate mounting bolts, not shown, which pass upwardly through suitably provided holes in the lower closure plate 49 and thread upwardly within the tapped apertures 54 of the pump cylinder 46, thereby holding the pump cylinder 46 securely to the lower closure plate 49.
  • a pumping piston 55 which forces liquid, in this instance oil, from the region 56 through the three openings 53 (Fig. 14) and into the interior 24 of the casing 15.
  • This pumped oil will enter a grid block 57, hereinafter described, to facilitate extinction of the arc established between the contacts 35, 43 during relatively low current values, when insuflicient pressure for interruption might otherwise exist within the grid block 57.
  • An annular spring base 58 (Fig. 2) is disposed interiorly within the piston 55, as shown in Fig. 2, and follow- 4 ing a predetermined time delay, as indicated by. the distance D (Fig. 2) to he traveled, picks up the piston 55 and drives it downwardly thereby giving rise to the aforementioned forced oil flow.
  • the annular spring base 58 serves as a seat for a pair of additional compression springs 59, 60, the upper ends of which bear against the upper interior end of the pump cylinder 46.
  • the cross-bar 7 has a contact tip 61 threaded therein, which engages the contact disc 44 and effects closing of the interrupter against the pressure exerted by the several springs 45, 59 and 60.
  • the cross-bar 7 moves downwardly, permitting the compression spring 45 to bring about rapid unimpeded separation between the contact rod 43 and the several contact fingers 35 establishing arcing therebetween.
  • the spring seat 58 initially moves downwardly, with the contact rod 43 because of the biasing action exerted by the compression springs 59, 60. This occurs only during the taking up of the lost-motion aiforded by the distance D, following which time the spring seat 58 picks up the piston 55 and drives the same downwardly.
  • the contact rod 43 however, because of the compression spring 45, moves freely downwardly unimpeded by the spring base 58 or the pumping piston 55.
  • the downward motion of the contact disc 44 is rapid because of the apertures therethrough and is guided by a contact guide casting 62, which is secured by mounting bolts, not shown, to the lower closure plate 49.
  • the lower closure plate 49 as was the case with the upper closure plate 12, has mounting bolts 14 associated therewith to secure it to the casing '15.
  • the downward opening motion of the lower movable contact 43 is limited by an inwardly extending flange portion 64 of the contact guide 62.
  • valves 26 are disposed at locations in the lower closure plate 49 adjacent the cutout portions 53 as shown in Fig. 2. Together with the upper valves 26 they permit a free flow of oil by convection upwardly interiorly within the casing 15 during the closed position, at which time the passage of load current through the interrupter will heat the surrounding oil.
  • the venting means provided by the two sets of normally open valves 26 associated with the upper and lower closure plates 12, 49 permits a ready flow of oil, by convection, through the interrupter. This enables cooling of the contact structure, and insures a supply of uncontaminated oil for a subsequent operation.
  • the grid block 57 includes a plurality of suitably configured insulating plates cemented together to form a unitary structure.
  • the top and bottom insulating plates 67 have merely a single centrally located hole 68 therein, with a groove 69 provided on one side of each plate 67 at opposite ends thereof.
  • the groove 69 cooperates with an insulating clamping plate 70 (Fig. 5) which is rotatably mounted on an insulating bolt 71.
  • suitable means effects upward travel of the lift rod 8, which correspondingly causes upward movement of the conducting cross-bar 7 with its contact tips 61.
  • the latter strike the contact discs 44 and move the same upwardly to effect contact closure while at the same time charging the several compression springs 45, 59 and 60.
  • the entire interrupter is composed of few parts, readily fabricated, and adaptable for effective operation.
  • the grid block 57 may be laterally removed from the unit 6 in the open position thereof by merely rotating one clamping plate 70 upon loosening the associated insulating bolt 71.
  • the stationary contact structure 82 may be reassembled in the reverse manner.
  • a liquid-break circuit interrupter including an arcextinguishing unit immersed in an arc-extinguishing liquid, said arc-extinguishing .unit including a hollow tubular insulating shell, said hollow tubular shell having a pair of support openings provided in the side walls thereof, a grid block having an arcing passage therein supported diametrically across said hollow tubular shell within said support openings, contact means including a rod-shaped movable contact for establishing an are within said are passage of the grid block, a lower substantially flat metallic closure plate for the arc-extinguishing unit, means detachably securing said substantially flat metaliic closure plate to the lower peripheral edge of said insulating hollow tubular shell, an inverted cup-shaped metallic operating cylinder extending upwardly within the arc-extinguishing unit from the lower closure plate and having at least one cut-out portion in the lower side wall thereof, means securing said inverted metallic cup-shaped operating cylinder to said substantially flat lower metallic closure plate so as to be removable there
  • a liquid-break circuit interrupter including an arcextinguishing unit immersed in an arc-extinguishing liquid, said unit including a cylindrical insulating casing, a grid block supported within openings in the side wall of the casing and extending diametrically across the interior of the casing, a lower metallic closure plate for the unit having one or more venting openings therein, an inverted cup-shaped operating cylinder disposed between the grid block and the lower closure plate, a pumping piston operable within the inverted cup-shaped operating cylinder for pumping liquid to assist in arc extinction, the inverted cup-shaped operating cylinder having at least one cut-out portion in the lower side wall thereof, normally-open valve'means extending through the lower metallic closure plate and situated adjacent the cut-out portion, and said inverted cup-shaped operating cylinder having one or more venting channels in the side wall thereof which register with said one or more venting openings in the closure plate for venting the top side of the pumping piston.
  • a liquid-break circuit interrupter including a tank containing an arc-extinguishing liquid, a terminal bushing extending within the tank and supporting an arc-extinguishing unit within the liquid, said unit including an in sulating cylindrical casing, 21.
  • top metallic closure plate attached to the interior end of the terminal bushing and supporting said insulating casing, a grid block supported within openings in the side wall of the casing and extendng diametrically across the interior of the casing, a lower metallic closure plate for the unit having one or more venting openings therein, an inverted cup-shaped operating cylinder disposed between the grid block and the lower closure plate, a pumping piston operable within the inverted cup-shaped operating cylinder for pumping liquid to assist in are extinction, and said inverted cupshaped operating cylinder having one or more venting channels in the side wall thereof which register with said one or more venting openings in the closure plate for venting the top side of the pumping piston.
  • a liquid-break circuit interrupter including a tank containing an arc-extinguishing liquid, a terminal bushing extending within the tank and supporting an arc-extinguishing unit within the liquid, said unit including an insulating cylindrical casing, a top metallic closure plate attached to the interior end of the terminal bushing and supporting said insulating casing, a grid block supported within openings in the side wall of the casing and extending diametrically across the interior of the casing, a lower metallic closure plate for the unit having one or more venting openings therein, an inverted cup-shaped operating cylinder disposed between the grid block and the lower closure plate, a pumping piston operable within the inverted cup-shaped operating cylinder for pumping liquid to assist in arc extinction, the inverted cup-shaped operating cylinder having at least one cut-out portion in the lower side wall thereof, normally-open valve means extending through the lower metallic closure plate and situated adjacent the cut-out portion, and said inverted cup shaped operating cylinder having one or more venting channels in the side wall
  • a liquid-break circuit interrupter including an arcextinguishing unit immersed in an arc-extinguishing liquid, said arc-extinguishing unit including an insulating cylindrical casing, a substantially flat lower metallic closure plate removably secured to the lower end of said cylindrical casing, said lower metallic closure plate having one or more venting apertures therein, an upstanding inverted cup-shaped operating cylinder supported upon the interior face of said lower closure plate and having one or more venting channels along the side wall thereof which register with said one or more venting apertures in'the lower closure plate, contact means for establishing an arc within said cylindrical casing, a pumping piston movable vertically within said inverted cup-shaped operating cylinder, and passage means interconnecting the working face of said pumping piston with said arc to facilitate the extinction thereof.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Switches Operated By Changes In Physical Conditions (AREA)
  • Circuit Breakers (AREA)
  • Folding Of Thin Sheet-Like Materials, Special Discharging Devices, And Others (AREA)
US574171A 1956-03-27 1956-03-27 Circuit interrupter Expired - Lifetime US2900478A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US574171A US2900478A (en) 1956-03-27 1956-03-27 Circuit interrupter
GB8783/57A GB806229A (en) 1956-03-27 1957-03-18 Improvements in or relating to electric circuit interrupters
CH351010D CH351010A (de) 1956-03-27 1957-03-26 Elektrischer Schalter
DEP24948A DE1149367B (de) 1956-03-27 1960-05-05 Einrichtung zum Zufuehren gefalteter Papierbogen

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US574171A US2900478A (en) 1956-03-27 1956-03-27 Circuit interrupter

Publications (1)

Publication Number Publication Date
US2900478A true US2900478A (en) 1959-08-18

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ID=24294963

Family Applications (1)

Application Number Title Priority Date Filing Date
US574171A Expired - Lifetime US2900478A (en) 1956-03-27 1956-03-27 Circuit interrupter

Country Status (4)

Country Link
US (1) US2900478A (de)
CH (1) CH351010A (de)
DE (1) DE1149367B (de)
GB (1) GB806229A (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3160728A (en) * 1960-09-30 1964-12-08 Westinghouse Electric Corp Sectioned molded insulating extinguishing unit for circuit interrupter with sections secured together by hot-wire technique
CN108390007A (zh) * 2018-04-24 2018-08-10 苏州聚天合金属科技有限公司 一种用于新能源电池电流自动切断的断电装置

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2409723A (en) * 1943-12-23 1946-10-22 Realty Ind Corp Oil circuit breaker
US2442010A (en) * 1943-12-24 1948-05-25 Westinghouse Electric Corp Circuit interrupter
US2462724A (en) * 1945-02-01 1949-02-22 Westinghouse Electric Corp Circuit interrupter
US2467542A (en) * 1945-06-02 1949-04-19 Allis Chalmers Mfg Co Arc extinguishing device
US2530952A (en) * 1947-04-16 1950-11-21 Westinghouse Electric Corp Circuit interrupter
US2673272A (en) * 1951-05-15 1954-03-23 Westinghouse Electric Corp Circuit interrupter
US2749412A (en) * 1953-09-17 1956-06-05 Gen Electric Electric circuit interrupter
US2780699A (en) * 1954-03-24 1957-02-05 Westinghouse Electric Corp Circuit interrupter
US2789186A (en) * 1955-05-31 1957-04-16 Gen Electric Electric circuit breaker

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE589475C (de) * 1930-05-16 1933-12-12 Brehmer Geb Verfahren und Maschine zum selbsttaetigen Zufuehren von geschlossenen Lagen in Draht- und Fadenheftmaschinen
CH324210A (de) * 1954-11-22 1957-09-15 Mueller Hans Anlegemaschine für die Papierindustrie

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2409723A (en) * 1943-12-23 1946-10-22 Realty Ind Corp Oil circuit breaker
US2442010A (en) * 1943-12-24 1948-05-25 Westinghouse Electric Corp Circuit interrupter
US2462724A (en) * 1945-02-01 1949-02-22 Westinghouse Electric Corp Circuit interrupter
US2467542A (en) * 1945-06-02 1949-04-19 Allis Chalmers Mfg Co Arc extinguishing device
US2530952A (en) * 1947-04-16 1950-11-21 Westinghouse Electric Corp Circuit interrupter
US2673272A (en) * 1951-05-15 1954-03-23 Westinghouse Electric Corp Circuit interrupter
US2749412A (en) * 1953-09-17 1956-06-05 Gen Electric Electric circuit interrupter
US2780699A (en) * 1954-03-24 1957-02-05 Westinghouse Electric Corp Circuit interrupter
US2789186A (en) * 1955-05-31 1957-04-16 Gen Electric Electric circuit breaker

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3160728A (en) * 1960-09-30 1964-12-08 Westinghouse Electric Corp Sectioned molded insulating extinguishing unit for circuit interrupter with sections secured together by hot-wire technique
CN108390007A (zh) * 2018-04-24 2018-08-10 苏州聚天合金属科技有限公司 一种用于新能源电池电流自动切断的断电装置

Also Published As

Publication number Publication date
CH351010A (de) 1960-12-31
GB806229A (en) 1958-12-23
DE1149367B (de) 1963-05-30

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