US2235901A - Electric circuit breaker - Google Patents

Electric circuit breaker Download PDF

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Publication number
US2235901A
US2235901A US173585A US17358537A US2235901A US 2235901 A US2235901 A US 2235901A US 173585 A US173585 A US 173585A US 17358537 A US17358537 A US 17358537A US 2235901 A US2235901 A US 2235901A
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United States
Prior art keywords
contact
cylinder
piston
extinguishing
pot
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Expired - Lifetime
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US173585A
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English (en)
Inventor
Ronnberg Daniel
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ABB Norden Holding AB
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ASEA AB
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Publication date
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    • 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
    • H01H33/94—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 solely due to the pressure caused by the arc itself or by an auxiliary arc
    • H01H33/96—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 solely due to the pressure caused by the arc itself or by an auxiliary arc the arc-extinguishing fluid being liquid, e.g. oil

Definitions

  • the are voltage tact pair intended for the closing of the circuit in turn is proportional to the length of the arc may also be so arranged that it serves for interand to the existing pressure. It is therefore clear ruption of the circuit in cooperation with the that the pressure arising in the first moment of C a P in the eXtinguiShing D closing of the circuit must be higher than the On the accompanying drawing several forms of pressure arising at interruption of the circuit, the invention are shown. Fig.
  • Fig. 5 shows the same arrangement as Fig. 4 but with an additional difierential piston which causes a flow of fluid against the arc between the contacts of the main contact pair.
  • Fig. 6 shows the same arrangement as Fig. 4 but with an additional difierential piston which causes a flow of fluid through the wall traversed by one of the contacts of the auxiliary contact pair.
  • Fig. 7 shows a combination of the arrange ments shown in Figs. 5 and 6 and is thus provided with two additional differential pistons.
  • Fig. 8 shows in detail a vertical section of the arrangement shown schematically in Fig. 5, and
  • Fig. 9 is a detail section of the arrangement shown in Fig. '7.
  • Fig. 10 is a detail section of a modified form of the arrangement schematically illustrated in Fig. 5.
  • I designates a. container filled with an insulating medium.
  • This container contains the two contact pairs and the bottom of the container is provided with an opening for the corn tact 2 operated by the operating mechanism of the breaker.
  • This contact extends in the closed position of the circuit breaker into the extinguishing pot 3, which consists of an upper cylinder 3 and a lower cylinder 5, which latter has a smaller diameter than the former.
  • the extinguishing pot is closed at its lower extremity by a bottom 6 and at the top by a cover 7.
  • a differential piston 8 which at the top has a collar 9, which fits the cylinder 4 and at the bottom has a collar I II, which fits the cylinder 5.
  • the bottom II of the differential piston is of insulating material and is provided with an opening I2 for the movable contact 2.
  • the stationary contact I3 is attached to a rod I4, which on the other end. carries a contact I5. This rod extends through an opening I6 in the cover I.
  • the rod I4 is surrounded by a cylinder I8, which at the top has a cover IS] with an opening 20 for the rod I l.
  • This cylinder has on the outer side a collar 2I, which can be pressed tightly against the cover 1.
  • stationary contact I3 is normally held in its lower position by means of a helical spring 22, which at the lower end rests on the piston I1 and at the upper end against the cover I9 of the cylinder I8.
  • This helical spring presses the cylinder I S upwards so that the collar 2I ispressed against the cover I.
  • the cylinder I8 is provided with openings 23, the purpose of which is described below.
  • the piston II has such a diameter that it tightly slides inside the cylinder I8.
  • the extinguishing pot 3 is supported by the leading-in conductor as by means of a disc 25 and insulating rods or an insulating cylinder 26. In the case that it is a cylinder, this is provided with openings on the side.
  • On the disc 25 a contact 21 is fastened, with which the contact I5 can be brought into engagement.
  • the arrangement acts in the following way.
  • the main contact 2 is moved upwards and is brought into engagement with the contact I3, which by a further movement of the contact 2 i moved upwards until the contact I5 auxiliary is caused to engage with the contact 27.
  • the contact I3 moves upwards, the fluid in the cylinder I8 is partly forced out through the openings 23 and thence through the space between the collar 2
  • the contact I3 is held back by the piston II.
  • the piston I'I tends to move downwards, a vacuum is created on the upper side of it, so that the cylinder I8 is raised a little, and the collar 2i is tightly pressed against the cover 7.
  • the opening of the circuit will therefore take place between the contacts 2 and I3 and the extinguishing pot will then act in the common manner, so that the pressure developed in it acts on the piston 8 which moves downwards thereby forcing the extinguishing medium from the space 32 through the opening I2 into the space 35, and at the same time extinguishing medium is forced out from the annular shaped space 33, which is in free communication with v
  • the openings in the cylinder 'l are so dimensioned that extinguishing medium'may stream out through them, but they are so restricted that at the breaking a suiiicient pressure can arise in the pot for moving the piston 8.
  • the downward motion of the contact I3 is effected by the action of the spring 22.
  • the container I is closed by a cover 34!, which i is provided with large openings for the escape of the gases.
  • a cover 34! which i is provided with large openings for the escape of the gases.
  • the movable contact 2 will in this case pass through the contact I3 up against the piston I! thus moving it and the rod I4 until the contact 55 engages with the contact 21.
  • 37 designates a cylinder with a cover 36.
  • the stationary contact is fastened to thi cover.
  • the cylinder 3'1 is provided with an inwardly bent edge 59, on which an insulating cylinder 38 is fastened.
  • This cylinder 38 has an intermediary wall 39, which is provided with an opening for a contact 42.
  • This contact is connected to a piston 43 movable in the cylinder 38, which piston also carries a contact i l, with which the contact 45 connected to the operating mechanism of the circuit can be caused to engage.
  • the contact 45 carries a piston 45, which fits the cylinder 38.
  • This piston is normally held in its upper position by means of a helical spring 59.
  • the cylinder 37 is provided on its side with openings 5
  • the contacts 52 and 44 with piston are normally pressed against the ring H by means of a helical spring 4?.
  • the arrangement according to Fig. 3 differs from the arrangement shown in Fig. 2 chiefly in that the differential piston is arranged around the extinguishing pot instead of inside it.
  • the differential piston is in this case formed by the cover 36, which is provided with an opening for the rod 65, and by the cylinder 31, which is provided with an inwardly directed collar 59, which tightly fits the cylinder 63.
  • This cylinder and the cylinder 60 with its collar are carried by the rod 65.
  • the arrangement acts in the same manner as the arrangement shown in the preceding figure, so that the piston 46 forces the fluid in the space 52 upwards, which fluid then actuates the piston 43 until the contact 42 engages the stationary contact 35. With this motion, the contact 42 moves through the opening 62 in the insulating intermediary wall 6
  • the space 52 is brought into communication with the space out side the cylinder 38 by the openings 40, so that the gases, which may be developed by an are between the contacts 44 and 45 easily can escape.
  • the pressure generated at the breaking is transmitted from the space 55 to the space 55, but also through the opening 62 to the spaces 54 and 51.
  • the pressure generated by the arc moves the piston 36, 31 against the action of the helical spring 50; so that the space 51 is decreased, and the fluid in this space will therefore be forced through the openings 58 into the space 54 and from there through the channels 62 into the space 55.
  • the motion of the contact 42 is limited by the ring 4
  • the arrangement may be such that the contact 42 in its end position rests in the opening in the bottom 64, but it is also possible to provide a form, where it moves so far that the opening in the intermediary wall 64 is free so that gas and liquid can escape through this opening.
  • designates a cylinder of insulating material, which at the lower end is provided with a bottom 12 also of insulating material, This is provided with an opening 13 for the movable contact 14.
  • the other contact of the contact pair in the extinguishing pot is designated by 15, and this contact is by means of the cylinder 16 connected with the piston 11, which is movable in the cylinder 18.
  • the piston 11 is actuated by a helical spring 8
  • the extinguishing pot is at the top closed by an intermediary wall 83 of insulating material, which wall has an opening 82 for one of the contacts 19 of the contact pair outside the extinguishing pot.
  • the other contact in this pair of contacts is designated by 84, and the space in which the contact pair 19, 84 is contained communicates by means of large openings 85 with the space outside the extinguishing pot.
  • This arrangement acts in the following way.
  • Fig. 5 differs from that of Fig. 4 in that the extinguishing pot is provided with a differential piston 9
  • This differential piston is normally held in its upper position by a helical spring 94, which at the lower end rests against the inwardly bent part 86 of the cylinder 1
  • This inwardly bent part carries also an insulating cylinder 81, which thus forms an extension of the extinguishing pot and is closed at the lower end by a bottom 12 of insulating material.
  • are openings 93 in order to allow the extinguishing medium below the flange of the differential piston to escape from the extinguishing pot.
  • the cylinder 81 instead of forming an extension downwards forms an extension.
  • and the differential piston is in this form arranged in the upper part of the extinguishing not so that b it a blow-out of the extinguishing medium through the opening 82 is effected.
  • the same extinguishing action is obtained between the contacts 14 and 15 as in the arrangement according to Fig. 4, but at the contacts 19 and 84 a considerably increased extinguishing action is obtained by means of the powerful stream of extinguishing medium forced out through the opening 82 by means of the piston 9
  • the arrangement according to Fig. 7 differs from the preceding one only in that the extinguishing pot is provided with two differential pistons 9
  • IOI designates the stationary contact in the extinguishing chamber and I02 the movable contact.
  • the stationary contact is, however, to a certain extent movable and is connected with a difierential piston described below.
  • the extinguishing pot itself is formed by an insulating cylinder I03, which is fastened to a metal cylinder I04, which in turn is fastened to an annular part I05 of metal, and this part is upwardly continued by an insulating cylinder I03, fastened to a cover I61 carrying the extinguishing pot.
  • a differential piston I90 consisting of an insulating cylinder I09 with bottom H0, which is also of insulating material and is provided with a flange III.
  • the intermediary part I05 consists of a ring I I2 and a ring H3, which by means of arms H4 carries a nave II 5.
  • a metal cylinder II 6 is inserted, and in this cylinder another cylinder II! with a tightening ring H8 moves.
  • the cylinder II! also fits in a tightening ring H9 of the nave II 5.
  • the cylinder II'I carries the stationary contact IIII, which in a known manner is formed as a sleeve contact, and further the cylinder IIT carries a pipe I20, which at the upper end is closed by one of the contacts I2I in the auxiliary contact pair outside the extinguishing pot.
  • the cylinder I06 there is an intermediary wall I22 with an opening I23, through which the auxiliary contact I2I can pass on its way to its counter-contact I24.
  • the space in the cylinder m6, which contains this contact is connected by large openings I25 with the space outside the cylinder I06, so that the contact pair IZI, I24 can be regarded as arranged outside the extinguishing pot.
  • a space I26 which is in communication with the space outside the extinguishing pot through channels I 21 in the arms H4.
  • These channels are provided with ball valves I28, which allow liquid to enter the space I26, but prevent liquid escaping from this space.
  • the ball valves are replaced by plugs which seep holes of suitable size.
  • the ball valves I28 consist of a cylinder I29, which at the outer end is provided with an inwardly directed rand I30. Immediately to this rand the cylinder is provided with two or several holes I3I, and in the cylinder there is a ball I32, and the motion of this ball is outwardly limited by the said rand, and its motion inwardly is limited by a pin I33.
  • the arrangement acts in the following way.
  • the movable contact I02 is moved up against the stationary contact IIII and then moves the cylinder III with pipe I20 and contact I2I upwards, so that the latter is caused to engage the contact I2 4.
  • the closing of the circuit will therefore take place between the two latter contacts, and if then an arc is ignited, the gases generated by it will escape through the openings I 25.
  • liquid is sucked into the space I 26 through the ball valves I28.
  • the pressure in the pot also acts on the upper side of the bottom in the cylinder III.
  • the cylinder II'I serves as a differential piston and tends to move downwards partly due to the pressure acting on it and partly due to the action of the helical spring I38.
  • This downward motion is, however, damped by the liquid in the space I 26, which liquid can escape only through the above mentioned seep holes in some of the arms H4, and by regulating these seep holes the damping of the motion of the cylinder I I I can be regulated.
  • the damping of the motion of the contact IIII is connected with the advantage that with small currents the distance between the contact WI and the bottom H0 a longer time is maintained at a large value than if the current is large.
  • the larger the current is the higher will be the pressure in the pot and the faster will the cylinder I I1 move downwards. In this way a smaller arc length is attained when the current is large, so that the energy developed by the arc during the interruption will be comparatively independent of the magnitude of the current traversing the circuit breaker when interruption takes place.
  • Fig. 8 The arrangement according to Fig. 8 is in some cases followed by the disadvantage that if an arc is ignited between the contacts I2I and I24 before the contact I2I has reached the opening I23, the pressure generated in the space I36 can be transmitted through the hole I23 and thus cause a motion of the piston H18.
  • Fig. 9 shows in detail a form which principally is the same as the form shown in Fig. 7.
  • a difierential piston is arranged in the upper part of the extinguishing pot. This piston will cause a stream of extinguishing medium through the hole I23 when the contact I2I is drawn away from this hole.
  • IIII designates the stationary contact and I82 the movable one.
  • the extinguishing pot is formed by a cylinder I04, which at the lower end carries a cylinder I03.
  • the cylinder IM is in turn carried by an intermediary part I consisting of a ring H2 and a ring H3.
  • the ring II3 carries by means of arms H4 a nave 7 H5.
  • a cylinder I40 which is provided with an intermediary wall I22 with an opening I23 for the contact I2I.
  • the cylinder I40 is at the upper end closed by the cover I01, but the space I36 between the intermediary wall I22 and the cover I01 communicates by large openings I25 with a space outside the extinguishing pot.
  • a differential piston I08 which consists of a cylinder I09 with bottom I I and flange III.
  • another difierential piston I4I through which the contact I2I passes.
  • the differential piston 508 is normally held in its upper position by means of the helical spring I31, and the differential piston MI is normally held in its lower position by means of the helical spring I43.
  • a cylinder H6 is fastened on the nave H .
  • another cylinder H1 is movable. This carries at the lower end the stationary contact IEII and is at the upper end provided with a tightening ring H8, which slides in the cylinder H6.
  • the nave H5 has at the lower end an inwardly bent part, which fits the cylinder H1, and further the cylinder H1 is provided with a rim II9, which tightening ring H8 slides in the cylinder H6.
  • the cylinder H8 may have an inner diameter decreasing downwards, which diameter at the lowermost part of the cylinder H8 is the same as the outer diameter of the ring IE9.
  • the contact IN is joined by means of the pipe I20 to the contact I2I.
  • the cylinder H1 with contact IIII is normally held in its lower position by means of the helical spring I38.
  • the arms H4 are all, or only some of them, provided with channels I21, by which the space inside the nave H5 is in communication with the space outside the extinguishing pot, and further the cylinder H6 is provided with openings I5I, which connect the space between the cylinder H6 and the cylinder II1 with the space inside the nave I I5.
  • This arrangement acts in the following way.
  • the contacts IOI and I02 are brought into engagement with each other, and when the contact I02 moves upwards the contact I2I also is moved upwards through the hole I23, so that it is brought into engagement with the contact I24.
  • the spring I38 is then pressed together.
  • the contact I02 When opening the circuit breaker, the contact I02 is pulled downwards and in the first moment the contacts WI and I02 are separated. By means of the pressure generated by the are formed between these contacts, the differential piston I08 is moved downwards and at the same time the difierential piston MI is moved upwards. The pressure generated by the are between the contacts IOI and I02 acts at the upper side of the cylinder H1 and tends to move this cylinder with the contact IOI and the contact I2I downwards. This motion is, however, damped by the liquid enclosed in the space below the rim H9 between this rim and the lower inwardly bent part of the nave I I5.
  • the contacts IOI and I02 When closing the circuit breaker, the contacts IOI and I02 at first are brought into engagement with each other, and firstly after this contact is completed, the contact I2I commences the motion upwards. When an arc is then ignited between the contacts I2I and I24, the gases generated by this are will escape through the openings I25.
  • Fig. differs from that of Fig. 9 in that the differential piston MI is replaced by an intermediary wall I45, which is provided with openings I46, the said openings being closed by back valves I41.
  • a pressure generated in the space I44 therefore can not be transmitted to the space I35 and cause a motion of the piston I08.
  • the pressure generated by the are between the contacts IOI and I02 can if it is sufficiently high allow a flow of liquid from the space I35 out through the openings I46 into the space I44 and from there through the opening I23.
  • an arc-extinguishing pot a main contact pair enclosed in the said pot, an auxiliary contact pair arranged outside the pot and series connected with the main contact pair, a dash pot mechanism retarding the opening of the auxiliary contact pair, an operating mechanism acting on the main contact pair, a spring acting on the auxiliary contact pair in the opening direction, and a difierential piston actuated by the pressure generated by the arc in the arc extinguishing pot, said piston being connected with one of the contacts in the auxiliary contact pair and acting in the opening direction.
  • an arc-extinguishing pot a main contact pair enclosed in the said pot, an auxiliary contact pair arranged outside the pot and series connected with the main contact pair, a dash pot mechanism retarding the opening of the auxiliary contact pair, an operating mechanism acting on the main contact pair, a spring acting on the auxiliary contact pair in the opening direction, a difierential piston actuated by the pressure generated by the arc in the arc extinguishing pot, said piston being connected with one of the contacts in the auxiliary contact pair and acting in the opening direction, and an insulating wall of the arc extinguishing pot provided with an opening traversed by the contact of the auxiliary contact pair connected with the differential piston.
  • an arc-extinguishing pot a main contact pair enclosed in the said pot, an auxiliary contact pair arranged outside the pot and series connected with the main contact pair, a dash pot mechanism retarding the opening of the auxiliary contact pair, an operating mechanism acting on the main contact pair, a spring acting on the auxiliary contact pair in the opening direction, a differential piston actuated by the pressure generated by the arc in the arc extinguishing pot, said piston being connected with one of the contacts in the auxiliary contact pair and acting in the opening direction, an insulating wall of the arc extinguishing pot provided with an Opening traversed by the contact of the auxiliary contact pair connected with the differential piston, and a further difierential piston arranged inside the extinguishing pot causin a flow of fluid in contact with the are between the main contacts.
  • an arc-extinguishing pot a main contact pair enclosed in the said pot, an auxiliary contact pair arranged outside the pot and series connected with the main contact pair, means for closing the main contact pair and afterwards the auxiliary contact pair, a differential piston actuated by the pressure generated by the arc in the arc extinguishing pot, said piston being connected with one of the contacts in the auxiliary contact pair and with the stationary contact of the main contact pair, an insulating wall of the arc extinguishing pot provided with an opening traversed by the contact of the auxiliary contact pair, actuated by the differential piston, a retarding device for the motion of the differential piston, a further diiferential piston arranged inside the extinguishing pot causing a flow of fluid in contact with the are between the main contacts, and a differential piston arranged inside the extinguishing pot, causing a flow of gases and liquid through the opening in the insulating wall of the pot, traversed by one of the contacts of the auxiliary contact pair
  • a main contact pair enclosed in each extinguishing pot an auxiliary contact pair arranged outside the extinguishing pot and series connected with the main contact pair, means for closing the main contact pair and afterwards the auxiliary contact pair, a differential piston actuated by the pressure generated by the arc in the arc extinguishing pot, said piston being connected with one of the contacts in the auxiliary contact pair and the stationary contact of the main contact pair, an insulating wall of the arc extinguishing pot provided with an opening traversed by the contact of the auxiliary contact pair actuated by the differential piston, a retarding device for the motion of the difierential piston, a further clifierential piston arranged inside the extinguishing pot causing a flow of fluid in contact with the arc between the main contacts, and a difierential piston arranged inside the extinguishing pot, causing a flow of gases and liquid through the opening in the insulating wall of the pot

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Circuit Breakers (AREA)
US173585A 1936-11-14 1937-11-09 Electric circuit breaker Expired - Lifetime US2235901A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE492486X 1936-11-14

Publications (1)

Publication Number Publication Date
US2235901A true US2235901A (en) 1941-03-25

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ID=20310638

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Application Number Title Priority Date Filing Date
US173585A Expired - Lifetime US2235901A (en) 1936-11-14 1937-11-09 Electric circuit breaker

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US (1) US2235901A (is")
BE (1) BE424598A (is")
FR (1) FR829062A (is")
GB (1) GB492486A (is")
NL (1) NL49564C (is")

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2420888A (en) * 1943-04-02 1947-05-20 Westinghouse Electric Corp Oil circuit interrupter
US2462724A (en) * 1945-02-01 1949-02-22 Westinghouse Electric Corp Circuit interrupter
US2462795A (en) * 1945-01-13 1949-02-22 Westinghouse Electric Corp Circuit interrupter
US2525494A (en) * 1942-11-11 1950-10-10 Westinghouse Electric Corp Circuit interrupter
US2572406A (en) * 1948-09-02 1951-10-23 Stulz Charles High-voltage oil circuit breaker
US2666118A (en) * 1950-06-29 1954-01-12 Westinghouse Electric Corp Circuit interrupter
US2855487A (en) * 1955-03-14 1958-10-07 Asea Ab Oil circuit breaker with two extinguishing chambers

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112735898B (zh) * 2020-12-01 2023-09-29 平高集团有限公司 一种弧触头及断路器

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2525494A (en) * 1942-11-11 1950-10-10 Westinghouse Electric Corp Circuit interrupter
US2420888A (en) * 1943-04-02 1947-05-20 Westinghouse Electric Corp Oil circuit interrupter
US2462795A (en) * 1945-01-13 1949-02-22 Westinghouse Electric Corp Circuit interrupter
US2462724A (en) * 1945-02-01 1949-02-22 Westinghouse Electric Corp Circuit interrupter
US2572406A (en) * 1948-09-02 1951-10-23 Stulz Charles High-voltage oil circuit breaker
US2666118A (en) * 1950-06-29 1954-01-12 Westinghouse Electric Corp Circuit interrupter
US2855487A (en) * 1955-03-14 1958-10-07 Asea Ab Oil circuit breaker with two extinguishing chambers

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Publication number Publication date
GB492486A (en) 1938-09-21
BE424598A (is")
NL49564C (is")
FR829062A (fr) 1938-06-10

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