Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
  • H01H9/30—Means for extinguishing or preventing arc between current-carrying parts
  • H01H9/32—Insulating body insertable between contacts

Definitions

• the present invention relates to a current threshold switching device comprising in an enclosure an input terminal, an output terminal and between them an electrical circuit comprising at least two separable contacts, as well as a rotary screen having a wall.
• the object of the present invention is in particular to produce a switch device with a rotary screen allowing simple and inexpensive manner to reliably cut off the arc and avoiding the risks of pollution and explosion.
• the cylindrical fixed wall delimits in the housing two volumes each located on one side of the wall, while a cylindrical lamellar space of notable length and low height is delimited between the radially inner face of the wall and the radially outer face of the annular sector, to define in said space a lamellar path capable of ensuring the rolling and cooling of the arc, the lamellar space communicating permanently with one at least two volumes to allow the expulsion of gases with expansion of said space to said volume.
• the arc plasma is therefore cooled along the concave fixed wall, the great length of the latter nevertheless being able to be accommodated in a relatively small space of the switch device thanks to the rounded shape of said wall.
• This rounded shape in combination with the pivot axis serving as a reference axis, allows slight variations in the radial clearance between the fixed wall and the annular sector without causing friction or jamming of the screen.
• the fixed wall may for example extend over at least about one quadrant downstream of the contact area in the direction of travel of the screen, in order to cause significant cooling of the arc.
• the annular sector of the screen forms a cap connected to the pivot axis by at least one connecting cheek in the form of a circular sector situated opposite a fixed cheek secured to the housing and separated from the latter by a lamellar space to determine a complementary lateral and lamel ⁇ communication path between the lamellar space and the expansion volume (s).
• the interior of the shell thus formed by the screen determines part of the expansion volume.
• the connecting cheek of the screen and the fixed cheek of the housing can advantageously have baffles in the form of ribs and annular cooperating notches for increasing the lateral lamellar path.
• Figure 1 is a partial view in longitudinal section of a switch device equipped with the screen according to the invention, and shown in its closed position of the contacts;
• Figure 2 shows the screen in its contact opening position
• Figure 3 shows another embodiment of the device
• Figure 4 is the section of the device of Figure 3 along the plane IV-IV passing through the pivot axis;
• FIG. 5 shows in perspective a double-cut device according to the invention.
• the switch device 10 illustrated in FIG. 1 is an intensity threshold device comprising in a housing 11 provided with an input terminal E and an output terminal S between which there is an electrical circuit 12 comprising at least two separable contacts; these contacts are shown diagrammatically in FIG. 1 by a fixed contact CF and a movable contact CM.
• the movable contact CM is connected to the terminal S and the fixed contact CF is connected to the input terminal E via a trip device 13.
• the trigger device 13 comprises a magnetic member with a movable armature, for example in the event of an overcurrent, to allow, on the one hand, the opening of the contacts by means of a mechanism 14 and, on the other hand, the movement of the screen using a propellant shown schematically in 15.
• the switch device 10 comprises a rotary screen 20 which has an annular sector 21 in the form of a cylindrical cap and two lateral cheeks 22, 23 for connection with pins 24, 25 allowing pivoting about an axis X-X.
• the screen 20 is molded in one piece from isolan ⁇ te material.
• Annular ribs 26 are provided on the outer face of the cheeks 22, 23, the function of which will be explained below.
• the cheeks of the annular sector in the present example cover an area greater than a quadrant.
• the housing comprises a fixed cylindrical wall 30 delimiting on each side a volume V ,, V 2 .
• a cylindrical lamellar space V 3 is generated by the displacement of the screen and is inserted between the volumes V and V 2 .
• the lamellar space V 3 of circumferential length L for example from 5 to 15 mm and of small thickness h, for example from 0.1 to 0.7 mm, is formed between the radially inner face 31 of the wall 30 and the radially outer face 27 of the annular sector 21 of the screen.
• the fixed wall 30 covers a space of approximately one quadrant downstream of the area of the contacts CF, CM with respect to the direction of movement of the screen when the contacts are opened, this direction being represented by the arrow F.
• the lamellar space V defines a path capable of ensuring the rolling, elongation and cooling of the arc and it communicates permanently with a chamber 32 provided in volume V, to allow the expulsion of gases with expansion of space V-. to chamber 32 and from it to the atmosphere.
• a lamellar space V. remains downstream of the contact zone during the entire movement of the screen over a length L 2 sufficient to avoid reflux of the arc.
• the fixed cylindrical wall 30 is preferably constituted (FIG. 3) by a partition 33 separating the interior of the housing 11 into a volume V- ⁇ comprising the chamber 32 and into a volume V- comprising a chamber 34; the partition 33 has an opening 35 which allows, on the one hand, the lifting of the movable contact CM towards the chamber 34, on the other hand, the expulsion of the gases of volume V, towards this same chamber in addition to their expulsion towards room 32.
• the housing 11 has, opposite the side cheeks 22, 23 of the screen, fixed cheeks 36, 37 extending over a circumferential distan ⁇ about equal to L, + L 2 e provided with annular and complementary ribs and grooves 38 ribs and grooves 26 of the rotary screen; the ring-shaped members "38 determine spaces lamellar laté- ral V-, V g respectively associated with the cheeks 22, 23 and of greater length than the radius of the annular sector.
• the switch device shown in FIG. 5 comprises a double-break member 40, more precisely with fixed contacts CF a , CF b and movable contacts CM a , CM. present both the particularity of being provided with two rotary screens 20a, 20b in accordance with the invention; these screens have a notch 28 for the passage of the contacts and they have their pivot axes combined in YY; they cooperate for example by means of a push or pull rod 41 with a single frame of the magnetic trip device 42. This results in great simplicity and a reduced size for the device.
• a drive face 50 it is advantageously provided on the screen 20 an element or a drive face 50 to cooperate with a drive means 41 associated with the magnetic trigger ( Figure 1), the latter therefore directly constituting the means of propulsion of the screen; preferably, a return device 16 is associated with the screen to return it to its initial position.
• the drive face 50 is for example advantageously located on the side opposite to the annular sector 27 with respect to the pivot axis X-X and at a relatively small radial distance from this axis relative to the radial distance from the annular sector.
• An energy storage system can be associated with the screen to constitute, in interdependence with the magnetic trip device 13, the means of propulsion of the screen.
• a drive face is provided on the rotary screen 20 to cooperate with an actuating face of the mechanism 14 for opening the contacts, this mechanism comprising an elastic triggering system .

Applications Claiming Priority (2)

Publications (2)

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ID=9303661

Family Applications (1)

Country Status (8)

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Family Cites Families (10)

• 1984
  • 1984-05-03 FR FR8406878A patent/FR2563939B1/fr not_active Expired
• 1985
  • 1985-04-30 ES ES542764A patent/ES8608224A1/es not_active Expired
  • 1985-05-03 DE DE8585902063T patent/DE3562839D1/de not_active Expired
  • 1985-05-03 WO PCT/FR1985/000105 patent/WO1985005218A1/fr active IP Right Grant
  • 1985-05-03 EP EP85902063A patent/EP0179834B1/de not_active Expired
  • 1985-05-03 JP JP60502078A patent/JPS62500333A/ja active Pending
  • 1985-05-03 US US06/835,866 patent/US4647741A/en not_active Expired - Fee Related
• 1988
  • 1988-08-15 SG SG60088A patent/SG60088G/en unknown

Non-Patent Citations (1)

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