FR2487113A1 - DOUBLE ROTATING ARC SWITCH - Google Patents

Abstract

THE INVENTION RELATES TO A DOUBLE ROTATING ARC SWITCH. A MAGNETIC BLOWING COIL 54 INCLUDES TWO ANNULAR ELECTRODES 56, 58, WHICH FRAME IT LATERAL AND TO WHICH ARE RESPECTIVELY CONNECTED THE INPUT AND OUTPUT OF COIL 54. COIL 54 IS INTERPOSED BETWEEN CONTACTS 36, 18 IN THE OPEN POSITION D 'A SWITCH, SUCH AS THE ARC FIRE BETWEEN THE SEPARATE CONTACTS 36, 18 IS TRANSFERRED TO THE ELECTRODES 56, 58 BY SUBDIVIDING INTO TWO DIVISIONAL ARCS, EACH SUBJECT TO THE MAGNETIC BLOWING OF THE COIL 54. THE ROTATING DIVISIONAL ARCS ARE FURTHER SUBJECT TO PNEUMATIC BLOWING BY THERMAL EXPANSION OF THE GASES FROM THE CUT-OFF CHAMBER 46 ESCAPING THROUGH THE TWO TUBULAR CONTACTS 16, 18 TO THE EXPANSION CHAMBERS 48, 50.

Description

DOUBLE ROTATING ARC SWITCH.

  The invention relates to a rotating arc switch

  having a sealed enclosure filled with a gas with

  in which are housed - a fixed or semifix contact,

  a sliding movable contact cooperating in a closed position

  with the fixed contact, - an annular blowing coil arranged to generate a transverse magnetic field in the zone-extension of the arc pulled during the separation of said contacts, - an annular electrode disposed in the vicinity of the arc for

  the latter, said electrode being electrically connected

  said coil to switch on said coil when transferring the arc to the electrode and

  root of the arc has a rotation on the annular electrode.

  The applicant has already proposed in her French patent application

  No. 80 06561 of 24-3-1980 a rotating arc switch

  of the kind mentioned, equipped with main contacts which

  parent without arc, prior to opening the arc contacts. In the closed position the movable contact passes through the orifice formed in the blowing coil and co-father by its outer periphery with a main contact shaped tulip. A semi-fixed contact accompanies the moving contact on part of its opening stroke so as to make an opening without arc of the main contacts, the arc being drawn

  during the separation of the semi-fixed contact and the

  bile. The fixed main contact is disposed at the rear of the blowing coil, which requires an increase in the stroke of the moving contact. The structure of the fixed assembly, constituted by the blowing coil and the fixed contacts, is not suitable for pneumatic blowing through the fixed contact.

  The present invention aims to improve the inter-

  said breaker, in particular to increase the performance of tcnsion by a series of two rooms and allow the realization of a switch of

  simple structure with increased performance.

  The switch according to the invention is characterized in that

  said coil is disposed in the separation zone of

  said contacts in open position and has a passage opening of the movable contact in the closed position and that said

  coil is flanked laterally by two annular electrodes

  electrically connected respectively to the input and

  at the exit of the coil, one of the electrodes being

  opposite the fixed contact and the other in relation to the

mobile touch in open position.

  The arc drawn during the separation of the contacts is subdivided into two divisional arcs anchored on the two electrodes

  framing the coil by putting it in circuit.

  Each divisional arch is subjected to the action of

  magnetic generation generated by the coil, and the half roots

  on the electrodes associated with the coil. The coil

  blowing circuit is automatically switched on as soon as

  line of the moving contact out of the coil. In position of

  closing the switch the coil is not powered.

  According to a development of the invention, the fixed contact

  carries a semi-fixed arc contact capable of accompanying, on a limited stroke, the moving contact to allow arcless separation of the main contacts constituted by

  a fixed contact tulip cooperating with the outer circumference

dull of mobile contact.

  According to another development of the invention, the fixed and movable contacts are of tubular shape to allow exhaust gases through the contacts and ensure a

  pneumatic blowing of the arches anchored on the contacts.

  The enclosure is advantageously subdivided by two partitions

  intermediaries in three chambers, the median chamber

  holding the contacts and constituting a breaking chamber communicating in the separating position of the contacts with the two adjacent expansion chambers. The action of the arches pulled between the contacts causes a thermal expansion of the gas of the interrupting chamber and an exhaust towards the expansion chambers through the tubular contacts. The internal diameter of the blowing coil is only slightly greater than the diameter of the tubular movable contact which passes through it in the closed position, so as to have a strong blowing magnetic field in the arc zone. Facing the annular electrodes flanking the

  of the coil are advantageously arranged

  equivalent diameter annular rings associated with

  fixed and mobile touch in order to capture the

  divisional arches in a manner known per se.

  Other benefits and features will come out more

  clearly from the following description of a mode of

  Embodiment of the invention, given by way of non-limiting example and shown in the accompanying drawing, in which Figure 1 is a schematic axial sectional view of a p &

  switch according to the invention, the left half-view

  presenting the switch in the closed position, and the half-view

  right representing this switch in the open position.

  In the figure, a casing 10 of cylindrical shape made of an insulating material, is sealed at its ends by bottoms 12, 14 constituting input and output terminals of the switch. The envelope 10 is filled with an electronegative gas, such as hexafluoride

  sulfur, under appropriate pressure. The bottom 12 is crossed

  in a sealed manner by a sliding rod 16 of control extended in its inner part to the casing 10

  by a tubular movable contact 18 presenting at its end

  mity an annular contact face 20. The movable contact

  tubular 18 is surrounded in its rear part by a sup-

  tubular port 22 whose end 24 is shaped in

  support of a tulip contact, designated by the

  general father 26. The tulip contact 26 comprises - in a manner well known to specialists a plurality of fingers

  28, distributed circumferentially around the collar

  24 and the movable tubular contact 18, a spring 30 holding the ends of the contact fingers 28 in contact with the collar 24 and a spring 32 holding the opposite ends of the contact fingers 28 in contact with the periphery of the tubular movable contact 18 The contact fingers extend into an annular arcuate track 34 projecting

  of the end 20 of the movable tubular contact 18 in position

  retracted opening of the latter.

  At the opposite end 14 is fixed, in a manner similar to that described above, a support 22 'carrying at its end a contact tulip 26' whose constituent elements - are identical to those of the contact tulip 26 and are affected of the same reference number-bearing an index. A semi-fixed tubular contact 36 is mounted with limited sliding in the support 22 ', a spring 38 cooperating with the semi-fixed contact 36 to urge the latter in the projecting position, represented on the right part of the figure, in which the face arc contact head 40 is set back from the annular ring 34 ', the contact fingers

  28 'being in support of the outer periphery of the semi-fixed contact 36.

  This last contact 36 can be pushed against the spring 38 in a retracted position, shown on the left part of the figure. Intermediate partitions 42, 44 subdivide the internal volume of the enclosure 10 into three

  chambers, in this case an interrupting chamber 46, deli-

  equipped by the partitions 42, 44, and two expansion chambers 48, 50 delimited respectively by the partition 42 and the

  bottom 14, and the partition 44 and the fondâ12. Contacts

  bile 18 and semi-fixed 36 as well as contact tulips

  26, 26 'are arranged coaxially in the chamber

  pure 46. The internal volumes of the mobile contacts 18 and

  semi-fixed 36 communicate via orifices 52, respectively

  with the expansion chamber 50 and with the chamber

  48, allowing exhaust gases to

  pure out of the break chamber 46 to the rooms

48, 50.

  In the central part of the interrupting chamber 46 is dis-

  placed a ring-shaped blowing coil 54, being interposed substantially at the same distance between the tulip contacts 26, 26 '. The annular lateral faces

  coil 54 are capped by electrodes 56, 58,

  each having a beaded annular track 60, 62

  respectively facing the arc crowns 34 'and 34. The coil 54 and the annular electrodes 56, 58 are tightened

  between flanges 64 by bolts 66, the assembly being as-

  subject to the intermediate partition 42 by one or more

  ports 68. A cylinder 70 made of a magnetic material with

  position of an insulating section or in a resistant insulating material

  both to the action of the arc, sheath the inner cylindrical face of the coil 54 and has an internal diameter slightly

  greater than that of the movable tubular contact 18 to allow

  to be a passage with weak game of the latter. The supply conductors of the coil 54 are electrically connected respectively to the annular electrode 56 and. at the electrode

  The screens 72 extending the annular electrodes

  laires 56, 58 are arranged in deflectors ionized gas by the arc.

  The switch according to the invention operates in the following manner. In the closed position, represented on the left-hand part of the figure, the mobile tubular and semi-fixed contacts 36 are abutted, the semi-fixed contact 36 being pushed back into position.

  position of withdrawal bringing into contact the periphery of the con-

  mobile touch 18 and the main contact in tulip 26 '. The

  almost all the current flows through the support 22 ', the con-

  tulip tact 26 ', the movable contact 18; the tulip contact 26 and the support 22, only a fraction of the current

  passing through the ends of the arc contact 20, 40. A

  downward lightening in the figure, from the control rod

  16 in a first stage causes the separation of

248 7113

  main tacts constituted by the contact tulip 26 'and the outer periphery of the movable contact 18, this separation being effected without arc. The semi-fixed contact 36 accompanies in its displacement the movable contact 18 and the current is switched on the arcing contacts 20, 40. At the end of this initial phase the semi-fixed contact 36 abuts and the

  continued movement of the movable contact 18 causes the separation

  ration of the arcing contacts 20, 40 with formation of an arc.

  The root of the arc quickly switches from semi-fixed contact

  36 on the annular ring 34. The movable contact 18 de-

  subsequently file in front of the annular electrode 60 and the elec-

  annular trode 62 by creating a subdivision of the arc into

  two divisional arcs anchored on the annular electrodes

  60, 62 activating the coil 54. At the end of the opening stroke the movable contact 18 is withdrawn from

  the ring annulus of arc 34 on which the arc.-

  The magnetic field generated by the blowing coil 54 causes a rotation of the roots of the divisional arcs

  on the annular electrodes 60, 62 and the annular crowns

  34, 34 '. The gases contained in the breaking chamber

  46 are subject to arc action and thermal expansion.

  causing an escape of gases through

  tubular contacts 18, 36 to the expansion chambers 48,50.

  The combined action of magnetic blow molding by rotating arcs and pneumatic blowing by thermal expansion of the gases and flow through the tubular contacts causes a rapid extinction of the arcs. Closing is done by

  a sliding movement in the opposite direction of the contact mo-

  bile 18, which comes first in contact with the annular face 40 of the semi-fixed contact 36, then in contact with the

  26 'contact tulip, the semi-fixed contact 36 being repouss-

  se in the retracted position. The opening of the main contacts

  This is done without a bow and thus without risk of erosion.

  The coil 54 is off in the closed position of

  the switch, its activation being automatic

during the opening.

  It is clear that the layout is not necessarily symmetrical, as described and illustrated by the figure

2487 1 13

  annexed, and that the coil 54 may comprise a circuit

  Magnetic reinforcement of the blowing field. The subdi-

  vision of the arc in two divisional arcs with insertion of the blowing coil can be used in combination with additional blowing means, either by thermal expansion of the gases, or by self-compression by piston and cylinder or autoaspiration. The switch can be

  without main contacts and / or annular crowns

  the roots of arches, the latter remaining anchored to the contacts throughout its duration. Although the fixed arrangement, illustrated by the figure, of the blowing coil is the simplest, it is conceivable to use a semi-fixed coil, which accompanies the moving contact in its opening movement on a limited stroke, so to generate the magnetic field more quickly. The contact or contacts are not necessarily hollow or sliding type, any other structure being conceivable. The performance of the switch corresponds to those of a

  two-chamber switch in series.

2487 1 13

Claims (9)

claims   1. A rotating arc switch having a sealed enclosure (10) filled with a gas with high dielectric strength, in which are housed: - a fixed or semi-fixed contact (36) - a movable contact (18) cooperating in position closing with the fixed contact (36),   an annular coil (54) for blowing arranged to   to generate a transverse magnetic field in the area of   the tension of the bow fired during the separation of the said   tacts, at least - / an annular electrode (56, 58) arranged in the vicinity   of the arc to capture the latter, said electrode being   electrically connected to said coil (54) to switch on said coil during transfer of the arc to the electrode and to subject the root of the arc to a rotation on the annular electrode, characterized in that said coil (54 ) is arranged in   the zone of separation of said contacts (18, 36) in position   open and has a passage opening of the movable contact (18) in the closed position and that said coil (54)   is flanked laterally by two electrodes (56, 58)   electrically connected respectively to the input and the output of the coil, one (56) of the electrodes being oriented opposite the fixed contact (36) and the other   (58) facing the movable contact (18) in the open position.   2. Switch according to claim 1, characterized in that the ends (40, 20) of said fixed contacts (36)   and mobile (18) of annular shape are arranged coaxially   to the blowing coil (54).   3. Switch according to claim 1 or 2, characterized in that the coil (54) is interposed substantially   in the middle between said contacts (18, 36) in position green.   4. Switch according to claim 1, 2 or 3, characterized   rised by the fact that an annular ring (34, 34 ') is associated with the fixed contact (36) and / or with the movable contact (18),   in order to protrude from the end (40, 20) of the   tact in the open position towards the electrode   (56, 58) and to capture the fired arc.   5. Switch according to claim 4, characterized in that the diameters of the annular ring (34, 34 ') and   of the associated annular electrode (56, 58) are equally equal.   6. Switch according to any one of the claims   previous, characterized in that said contacts (18,36) are of tubular shape to allow an escape of gases through said contacts out of the extension zone of the bow.   Switch according to claim 6, characterized in that   what said enclosure (10) comprises two partitions inter-   mediates (42, 44) flanking the zone of extension of the arc so as to constitute an interrupting chamber (46) flanked by two expansion chambers (48, 50) and a blowing by thermal expansion of the gases of the chamber breaking (46)   through the two contacts (18, 36).   8. Switch according to any one of the claims   previous, characterized in that said contacts (36, 18) cooperate by abutting, the fixed contact (36) being mounted   with limited sliding to allow the commitment of the   cylindrical tower of the movable contact (18) in a tulip of main contact (26 ').   9. Switch according to any one of the claims   preceding, characterized by a shielding screen (70)   dull of the coil (54), interposed without a solution of continuity   between the two annular electrodes (56, 58).