US2964605A - Fluid pressure operated circuit breaker pole units - Google Patents

Fluid pressure operated circuit breaker pole units Download PDF

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Publication number
US2964605A
US2964605A US610868A US61086856A US2964605A US 2964605 A US2964605 A US 2964605A US 610868 A US610868 A US 610868A US 61086856 A US61086856 A US 61086856A US 2964605 A US2964605 A US 2964605A
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United States
Prior art keywords
pressure
valve
contacts
operating
fluid
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Expired - Lifetime
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US610868A
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English (en)
Inventor
Schulz Richard
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Voigt and Haeffner AG
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Voigt and Haeffner AG
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Classifications

    • 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
    • H01H33/02—Details
    • H01H33/28—Power arrangements internal to the switch for operating the driving mechanism
    • H01H33/30—Power arrangements internal to the switch for operating the driving mechanism using fluid actuator
    • H01H33/32—Power arrangements internal to the switch for operating the driving mechanism using fluid actuator pneumatic
    • 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
    • H01H33/02—Details
    • H01H33/53—Cases; Reservoirs, tanks, piping or valves, for arc-extinguishing fluid; Accessories therefor, e.g. safety arrangements, pressure relief devices
    • H01H33/56—Gas reservoirs
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7781—With separate connected fluid reactor surface
    • Y10T137/7784—Responsive to change in rate of fluid flow
    • Y10T137/7785—Valve closes in response to excessive flow

Definitions

  • each pole unit is provided with a plurality of pairs of cooperating relatively movable contacts adapted to form multibreaks upon separation thereof.
  • circuit breakers of this type operation of the pairs of relatively movable contacts is preferably elfected by fluid under pressure, e.g. air under pressure, and in circuit breakers of this type the series arcs formed upon separation of pairs of cooperating contacts may be extinguished by blasts of air.
  • circuit breakers having serially related multibreak-forming contact means in each pole thereof, and having pressure-responsive operating means for said contact means closing said contact means upon a reduction in pressure, wherein accidental closing of the circuit as a result of a defect in the compressed uid operating system is positively precluded.
  • Another object of the invention is to provide a circuit breaker operating system wherein accidental losses of fluid under pressure are localized, and thus precluded from causing a drop of pressure throughout the system which would result in a faulty operation of the circuit breaker.
  • Another object of the invention is to provide a circuit breaker operating system comprising automatic valve means responsive to fluid leakage for selectively isolating defective portions of the system from the portions thereof which are intact.
  • Still another object of the invention is to provide a circuit breaker operating system having selective automatic leakage responsive valve means and having, in addition thereto, manually operable control means for causing opening of said valve means in spite of the prevalence of low pressure conditions normally causing automatic closing of the aforementioned valve means.
  • lt is another object of the invention to provide means resulting in selective closing of but a portion of the serially related contacts provided in a pole unit of a circuit breaker having a pneumatic operating system.
  • FIG. 1 shows a circuit-breaker pole unitin part in side elevation and in part in vertical section
  • Fig. 2 shows mainly a vertical section through one of the housings 2 of Fig, l, some of the parts included in Fig. 2 being shown in side elevation, and
  • Fig. 3 is a top-plan view of the structure of Fig. 2 showing the association of two housings 2 of Fig. 1 with one common supporting column.
  • FIG. l reference numeral 1 has been applied to indicate three hollow insulating columns of which each supports two operating mechanism receiving cham-4 bers or cases 2 on the top portion thereof.
  • the parts accommodated in cases 2 are more fully shown in Fig. 2.
  • Each of the operating mechanisms housed in each of the chambers or cases 2 may comprise a uid motor of the cylinder-and-piston-type.
  • Each chamber or case 2 supports a hollow horizontal insulator 2a as shown in Fig. 3 and the contact operating mechanisms in the two cases on top of each column 1 are adapted to operate two pairs of relatively movable contacts forming two breaks in series upon separation thereof.
  • the pole structure illustrated comprises three insulating columns 1, two times three, i.e.
  • Each supporting insulator 1 is mounted upon a separate storage tank 3 for air under pressure.
  • Manifold 5 is connected to a source of fluid under pressure (not shown), such as a compressor system, and provided with three tap conduits 4, each connected to one of tanks 3.
  • Each conduit 4 is controlled by an automatic valve 6 adapted to be operated by motor means associated with it, eg. fluid motors 8.
  • Each fluid motor 8 comprises a piston 7 having a piston rod for operating one of valves 6 and a spring 7a biasing piston 7 downwardly, i.e. to the valve open position thereof.
  • Each piston 7 is provided with a stem 7b supporting a contact bridge for an auxiliary switch 13..'
  • Each auxiliary switch 13 controls the circuit of a signalling device A13a indicating whether valves 6 are in the open or closed position thereof.
  • Probe or venting conduits 9v connect the space of each cylinder of each fluid motor 8 situated above piston 7 to the lower end of each of the insulating columns 1.
  • Manifold 10 is adapted to supply to the space of each cylinder of each uid motor 8 situated below piston 7 fluid under pressure derived from manifold 5. To this end manifolds and are connected by a valve or cock 11.
  • Valve or cock 11 is a manually operable three-way-valve. Normally valve 11 is in the position shown, admitting air under pressure from manifold 5 to manifold 10.
  • manifold 5 By operation of valve 11 manifold 5 may be sealed off, and manifold 10 vented to atmosphere.
  • the circuit breaker may be provided with a pneumatic control system for effecting manual opening and closing and for automatic tripping thereof.
  • the air under pressure required for such a control system is taken from the right end of manifold 10, indicated by reference numeral 12.
  • Reference numeral 14 has been applied to indicate a pressurel relief valve, and reference numeral 15 has been applied to indicate a pressure gage both connected to manifold 5.
  • FIG. 2 the structure shown therein is prior art disclosed in British Patent 713,798 and ULS. Patent 2,724,757.
  • the insulating column 1v supports two chambers 2v made of metal, one arranged in front and one arranged on the rear of column 1. Chambers 2 are connected in series. As shown in Fig. 3 the left side of the front chamber 2 and the right side of the rear chamber 2 are provided with bushings 2a through which connector studs 2d extend into the inside of chambers 2.
  • the axially inner ends of studs 2d support fixed contacts 16 adapted to cooperate with movable tubular contacts 17.
  • Each movable contact 17 supports a piston 18 biased by a helical spring 19 tending to move the contact to the closed position thereof, i.e.
  • Blast valve 20 is adapted to be operated by a fluid motor comprising cylinder 31 and piston 21 under the bias of helical spring 22 tending to move blast valve 21B to the closed position thereof.
  • Numeral 23 has been applied to indicate an orlce in housing 2 through which air under pressure forming an arc-extinguishing blast may escape upon separation of contacts 16, 17 and opening of blast valve 20.
  • Piston 21 may be operated by air under pressure admitted to it through control conduit 24 which may be connected to manifold 12 (see Fig. 1) by means of a trip and venting valve (not shown).
  • the space 25 to the right of piston 18 is connected by duct 26 to a dual position valve 27 operable by means of rod 29. In the position of valve 27 and rod 29 shown in Fig.
  • valve 27 connects duct 26 with pipe line 28 and, therefore, the pressure in the above-mentioned space 25 is equal to the pressure in that part of chamber 2 adjacent contacts 16, 17, i.e. that part of chamber 2 which is separated from the other part by the cylinder structure inside of which piston 18 operates.
  • the tap-like movable valve element thereof closes a venting port provided in the housing of valve 27.
  • Rod 29 is under the control of a pressure responsive element 30 causing the rod to move from right to left if there is pressure in pipe lines 24 and 24a.
  • An adjustable needle valve 32 connects pipe line 24a with that portion of cylinder 31 situated to the left of piston 21. Needle valve 32 thus controls the flow of air under pressure from pipe lines 24, 24a to the left end of cylinder 31.
  • Numeral 33 has been applied to indicate a check valve for venting the part of cylinder 31 situated to the left of piston 21 when the pressure in control pipe line 24 drops incdent to a closing operation of the circuit breaker pole unit.
  • Closing of the circuit breaker pole unit is effected by p venting pipe line 24 to atmosphere. This results in moving control rod 29 from left to the right position shown in Fig. 2, whereby air under pressure is admitted to space Z5 through pipe line 28, valve 27 and duct 26. As a result, piston 18 and movable contact 17 are moved from right to left, i.e. to the closed position shown in Fig. 2.
  • my invention comprises pressure-responsive means including a'valve to selectively sever the faulty portion of a pneumatic circuit breaker operating system from the sound portion thereof.
  • the probe conduit 9 may be connected to any point where a drop'in pressure will occur as a result of loss of uid under pressure.
  • Probe conduit 9 might be connected directly to chamber 2, or to tank 3.
  • To connect probe conduit 9 to the bottom of column 1 is preferable since this is the point at ground potential closest to chamber 2.
  • the selectivity which I have achieved is predicated on associating a plurality of separate systems of iluid under pressure with each pole unit of the circuit breaker, each of said plurality of separate systems of tluid under pressure comprising a separate storage tank 3.
  • While this invention is not limited to air blast circuit breakers, it is preferably embodied in circut breakers of that type. To establsh an arc extinguishing air blast air under pressure is supplied directly from the top of hollow columns 1 to the space in chambers or cases 2 where cooperating contacts 16, 17 are arranged.
  • a high voltage circuit breaker pole unit the combination of a plurality of pairs of cooperating separable contacts adapted to be serially connected into an electric circuit, a plurality of systems of fluid under pressure, a plurality of fluid-pressure-responsive contact operating means each adapted to be supplied with fluid under pressure from one of said plurality of systems, each of said plurality of contact operating means being operatively related to at least one of said plurality of pairs of contacts and adapted to maintain said one of said plurality of pairs of contacts separated in the presence of a predetermined tluid pressure in one of said plurality of systems and to close said one of said plurality of pairs of contacts in the absence of said predetermined uid pressure in said one of said plurality of systems, a plurality of tanks each forming part of one of said plurality of systems, a manifold for supplying fluid under pressure to each of said plurality of tanks, a plurality of valves each connecting one of said plurality of tanks to said manifold, and a plurality of controls one for each of said plurality
  • a high voltage circuit breaker pole unit the combination of a plurality of storage tanks for air under pressure, a plurality of hollow insulating columns eachv mounted on one ⁇ of said plurality of tanks, pairs of cooperating separable contacts adapted to be serially connected into an electric circuit, supported by said plurality of columns, a plurality of air-pressure-responsive contact operating means each arranged on and connected to one of said plurality of columns, each of said plurality of contact operating means being operatively related to at least one of said pairs of contacts and each adapted to maintain said one of said pairs of contacts separated in the presence of a predetermined air pressure at one of said plurality of columns and to close said one of said pairs of contacts in the absence of said predetermined air pressure at said one of said plurality of columns, a manifold for supplying air under pressure to each of said plurality of tanks, a plurality of valves each connecting one of said plurality of tanks to said manifold, a plurality of valve operating motors one for each of said plurality of valves, a plurality of
  • a high voltage circuit breaker pole unit the combination of a plurality of pairs of cooperating separable contacts adapted to be serially connected into an electric circuit, a plurality of contact-operating fluid motors each operatively related to one of said plurality of pairs of contacts, each of said plurality of fluid motors being adapted to maintain said one pair of contacts separated in the presence of a predetermined amount of fluid pressure, means for closing each of said plurality of pairs of contacts in the absence of said predetermined amount of fluid pressure, a plurality of storage vessels for fluid under pressure each connected to one of said plurality of contact-operating uid motors, a source of iluid under pressure for supplying fluid under pressure to each of said plurality of vessels, a plurality of valves each connecting said source to one of said plurality of vessels, a plurality of valve-operating fluid motors one for each of said plurality of valves, each of said plurality of valve-operating lluid motors comprising a differential piston having a valve-open-position and
  • one of said plurality of contact-operating fluid motors to one of said plurality of valve-operating uid motors to cause said differential piston of one of said plurality of valve-operating lluid motors to move to said valve-closed-position thereof in response to accidental venting of one of said plurality of contactoperating fluid motors.
  • a pluarlity of contact-operating fluid motors each operatively related to one of said plurality of pairs of contacts maintaining said one of said plurality of pairs of contacts separated in the presence of a predetermined fluid pressure and closing said one of said plurality of contacts in the absence of said predetermined fluid pressure, a source of uid under pressure, means for supplying uid under pressure from said source to said plurality of contact-operating uid motors, said fluid supplying means comprising a plurality of valves each controlling the supply of fluid under pressure from said source to one of said plurality of contact-operating uid motors,
  • a plurality of valve-operating uid motors one for each of said plurality of valves, a plurality of differential pistons each in one of said plurality of valve-operating uid motors, each of said plurality of differential pistons being movable to a valve-open-position and to a valveclosed-position, a plurality of springs each biasing one of said plurality of differential pistons to said valve-openposition thereof, a plurality of conduits for fluid under pressure each connecting one of said plurality of contactoperating fluid motors to one of said valve-operating uid motors tending to equalize the uid pressure at one of each of said plurality of contact-operating uid motors and at one of each of said plurality of valve-operating fluid motors, and conduit means for admitting fluid under pressure from said source to each of said plurality of differential pistons tending to move each of said plurality of differential pistons to said valve-closed-position thereof.
  • a high voltage circuit breaker pole unit as specified in claim 4 comprising a plurality of auxiliary switches each under the control of one of said plurality of differential pistons.
  • a high voltage circuit breaker pole unit the combination of a plurality of pairs of cooperating separable contacts adapted to be serially connected into an electric circuit, a plurality of contact-operating fluid motors each operatively related to one of said plurality of pairs of contacts maintaining said one of said plurality of contacts separated in the presence of a predetermined iiuid pressure and closing said one of said plurality of contacts in the absence of said predetermined iluid pressure, a plurality of storage vessels for fluid pressure each connected to one of said plurality of contact-operating fluid motors, a manifold for supplying fluid under pressure to each of said plurality of vessels, a plurality of valves each controlling the supply of fluid under pressure from said manifold to one of said plurality of storage vessels, a plurality of valve-operating iiuid motors one for each of said plurality of valves, a plurality of pistons one in each of said plurality of valve-operating fluid motors, each f said plurality of pistons having a valve
  • a high voltage circuit breaker pole unit the combination of a plurality of pairs of cooperating separable contacts adapted to be serially connected into an electric circuit, a plurality of contact-operating fluid motors each operatively related to one of said plurality of pairs of contacts maintaining said one pair of contacts separated in the presence of a predetermined uid pressure and closing said one pair of contacts in the absence of said predetermined uid pressure, a plurality of storage vessels for uid under pressure each connected to one of said plurality of contact-operating tluid motors, a first manifold for supplying fluid under pressure to said plurality of vessels, a plurality of valveseach connecting said first manifold to one of said plurality of storage vessels, a plurality of valve-operating uid motors one for each of said plurality of valves, a plurality of pistons one in each of said plurality of valve-operating fluid motors, each of said plurality of pistons being movable to a valve-open-position and to
  • a high voltage circuit breaker pole unit as specified in claim 7 comprising a three-way valve adapted to supply said second manifold with uid under pressure from said first manifold and to dump iluid under pressure from said second manifold.
  • a circuit breaker comprising a plurality of pairs of co-operating contacts, means for serially connecting said plurality of pairs of contacts into an electric circuit, a plurality of systems containing fluid under pressure, one associated with each of said plurality of pairs of contacts, a common supply of fluid under pressure for said plurality of systems, a plurality of automatic valves each controlling the admission of iiuid under pressure from said source to one of said plurality of systems, a plurality of fluid motors each operatively related to one of said plurality of pairs of contacts, each of said plurality of iiuid motors being adapted to maintain said one of said plurality of pairs of contacts separated in the presence of a predetermined pressure in one of said plurality of systems and each of said plurality of fluid motors comprising means for closing said one of said plurality of pairs of contacts in the absence of said predetermined pressure, and a plurality of pressure-sensing means each associated with one of said plurality of systems and each controlling one of said plurality of automatic valves to cause selective closing thereof

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  • Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
US610868A 1955-09-22 1956-09-19 Fluid pressure operated circuit breaker pole units Expired - Lifetime US2964605A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEV9507A DE1020710B (de) 1955-09-22 1955-09-22 Druckluftschalter mit Vielfachunterbrechung pro Pol

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US2964605A true US2964605A (en) 1960-12-13

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US610868A Expired - Lifetime US2964605A (en) 1955-09-22 1956-09-19 Fluid pressure operated circuit breaker pole units

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US (1) US2964605A (de)
BE (1) BE551063A (de)
CH (1) CH344467A (de)
DE (1) DE1020710B (de)
FR (1) FR1156275A (de)
NL (1) NL96963C (de)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3073932A (en) * 1958-09-24 1963-01-15 Voigt & Haeffner Ag Pneumatic controls for high-voltage air blast circuit breakers
US3087035A (en) * 1959-03-20 1963-04-23 Asea Ab Fluid operated circuit breaker
US3097280A (en) * 1958-12-23 1963-07-09 Siemens Ag Partitioned gas-filled electrical apparatus
US3141942A (en) * 1959-08-13 1964-07-21 Asea Ab Control means for air blast circuit breakers
US3171937A (en) * 1962-05-07 1965-03-02 Westinghouse Canada Ltd Arc-extinguishing structure for compressed-gas circuit interrupter
US3198916A (en) * 1962-11-29 1965-08-03 Ite Circuit Breaker Ltd Vented movable resistor contact for air blast circuit breakers
US3622726A (en) * 1967-03-23 1971-11-23 Merlin Gerin Gas blast circuit breaker with contact closing low pressure responsive safety device
US4041264A (en) * 1974-09-30 1977-08-09 Asea Aktiebolag Operating device for a contact device for a pre-insertion resistor in a high-voltage circuit breaker

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1207992B (de) * 1958-08-01 1965-12-30 Bbc Brown Boveri & Cie Druckluftschalter mit Einfach- oder Mehrfachunterbrechung pro Pol
DE1216408B (de) * 1962-02-27 1966-05-12 Continental Elektro Ind Ag Hochspannungsdruckgasschalter
FR2080097A5 (de) * 1970-02-23 1971-11-12 Merlin Gerin
FR2461887A1 (fr) * 1979-07-16 1981-02-06 Alsthom Cgee Dispositif de vidange d'un reservoir de gaz comprime relie a un disjoncteur pneumatique

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2148410A (en) * 1937-11-15 1939-02-21 Automatic Valve Controller Com Pipe line automatic valve control
US2387960A (en) * 1942-10-10 1945-10-30 Westinghouse Electric Corp Operating mechanism
US2472070A (en) * 1946-04-15 1949-06-07 Phillips Petroleum Co Pressure controlled liquid outlet valve
US2491112A (en) * 1947-07-05 1949-12-13 Allis Chalmers Mfg Co Gas blast breaker having two tanks and a tank interconnecting valve
GB718401A (en) * 1951-05-25 1954-11-10 Vickers Electrical Co Ltd Improvements relating to gas-blast circuit-breakers
US2747055A (en) * 1952-05-31 1956-05-22 Asea Ab High tension circuit breakers
US2748226A (en) * 1953-02-26 1956-05-29 Westinghouse Electric Corp Compressed-gas circuit interrupter

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2148410A (en) * 1937-11-15 1939-02-21 Automatic Valve Controller Com Pipe line automatic valve control
US2387960A (en) * 1942-10-10 1945-10-30 Westinghouse Electric Corp Operating mechanism
US2472070A (en) * 1946-04-15 1949-06-07 Phillips Petroleum Co Pressure controlled liquid outlet valve
US2491112A (en) * 1947-07-05 1949-12-13 Allis Chalmers Mfg Co Gas blast breaker having two tanks and a tank interconnecting valve
GB718401A (en) * 1951-05-25 1954-11-10 Vickers Electrical Co Ltd Improvements relating to gas-blast circuit-breakers
US2747055A (en) * 1952-05-31 1956-05-22 Asea Ab High tension circuit breakers
US2748226A (en) * 1953-02-26 1956-05-29 Westinghouse Electric Corp Compressed-gas circuit interrupter

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3073932A (en) * 1958-09-24 1963-01-15 Voigt & Haeffner Ag Pneumatic controls for high-voltage air blast circuit breakers
US3097280A (en) * 1958-12-23 1963-07-09 Siemens Ag Partitioned gas-filled electrical apparatus
US3087035A (en) * 1959-03-20 1963-04-23 Asea Ab Fluid operated circuit breaker
US3141942A (en) * 1959-08-13 1964-07-21 Asea Ab Control means for air blast circuit breakers
US3171937A (en) * 1962-05-07 1965-03-02 Westinghouse Canada Ltd Arc-extinguishing structure for compressed-gas circuit interrupter
US3198916A (en) * 1962-11-29 1965-08-03 Ite Circuit Breaker Ltd Vented movable resistor contact for air blast circuit breakers
US3622726A (en) * 1967-03-23 1971-11-23 Merlin Gerin Gas blast circuit breaker with contact closing low pressure responsive safety device
US4041264A (en) * 1974-09-30 1977-08-09 Asea Aktiebolag Operating device for a contact device for a pre-insertion resistor in a high-voltage circuit breaker

Also Published As

Publication number Publication date
BE551063A (de) 1956-09-29
NL209881A (de) 1960-09-15
CH344467A (de) 1960-02-15
NL96963C (de) 1961-02-15
DE1020710B (de) 1957-12-12
FR1156275A (fr) 1958-05-14

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