FR2920251A1 - Current interrupting device for e.g. contactor, has sheath extended by cylindrical part defining transmission part, and strips fitted in groove formed in cylindrical part extending sheath irrespective of position in movement of control part - Google Patents

Abstract

The device (100) has an insulating sheath extended by a cylindrical part (27) defining an insulating transmission part (30). The part (30) has an elongated and cylindrical body (32) and ends (34, 36) connected to a movable undervoltage contact (16) of an insulating vacuum tube (4) and a control part (48), respectively. The part (30) has peripheral strips extended towards the end (34) along longitudinal direction of the body. The strips are fitted in an end peripheral groove (272) that is formed in the part (27) extending the sheath irrespective of a position in movement of the part (48).

Description

CUTTING DEVICE FOR ELECTRICAL SWITCHING EQUIPMENT

  TECHNICAL FIELD The present invention relates to the technical field of switching electrical equipment such as circuit breakers, switches, contactors or disconnectors, in particular medium or high voltage electrical equipment. More specifically, the invention relates to a cut-off device for a high or medium voltage switchgear, such as a circuit breaker, a switch, a contactor or a disconnector, said cutoff device comprising a vacuum interrupter in which two contacts are arranged in a longitudinal direction (Z), at least one of which is moveable, said device comprising an insulating envelope which is extended by a cylindrical part which delimits a well and an insulating transmission piece transmitting a movement between a workpiece control device at the earth potential and the moving contact under voltage, said transmission insulating member having a substantially elongated body, a first end connected to said movable contact and a second end connected to said control part. STATE OF THE PRIOR ART Conventionally, an electrical switchgear under vacuum, such as a circuit breaker, a switch, a contactor or a disconnector, comprises a vacuum insulating bulb in which are arranged two remote contacts one of the other, at least one of the two contacts being mobile. These two contacts extend outwardly of the vacuum interrupter for connection to a portion of the electrical circuit.

  The switchgear also has motion transmitting means for transmitting motion between a ground potential control member and a live switching member. These transmission means act to bring the contacts closer to each other in order to allow the passage of current between them, or to separate the two contacts from one another in order to interrupt this passage of the current. It is known that the motion transmission means comprise at least one transmission piece which is insulating and whose shape, defined as the shortest distance in the gas between conducting parts under different potentials, also called spark line, is established. in order to avoid any arc striking between these conductive parts. The document FR 2 807 203 (Schneider Electric) describes an electrical switchgear comprising a vacuum interrupter. A fixed contact is disposed at one end of the vacuum bottle and a movable contact is disposed at its other end. The motion transmission means comprise a pivoting lever actuated by a control member, and. an insulating arm. The insulating lever acts on one end of the insulating arm via a contact pressure spring.

  The other end of the insulating arm is connected to a metal conductive rod which carries the movable contact. During pivoting of the pivoting lever, the insulating arm is moved in translation and transmits this movement to the metal conductive rod which moves in translation parallel to itself and to the longitudinal direction of the vacuum bulb, so as to bring it closer to or move the moving contact away from the fixed contact. A disadvantage of the switchgear that has just been described lies in the fact that the motion transmission means have a large size, especially in the longitudinal direction of the insulating arm, and therefore the switchgear present also a large size. SUMMARY OF THE INVENTION An object of the present invention is to provide a switchgear for an electrical switchgear which has a reduced length relative to the length of the cutoff devices of the prior art, without reducing the length of the switchgear. the spark line. These objects are achieved, according to the invention, by the fact that the insulating transmission part comprises, at the level of its second

  end, one or more peripheral fins extending towards the first end of the transmission part in a longitudinal direction (Z) of said body, and. in that the fins remain nested in recesses formed in the cylindrical portion which extends the insulating envelope, regardless of the position in the movement of the control part. With such a device, the spark line, namely the path of the electric arc to the shortest in the air between live metal parts and parts at the potential of the earth, is increased by the interlocking of the fins in the evidently formed in the cylindrical portion which extends the insulating envelope. Preferably, said transmission insulating part is arranged in such a way that its longitudinal direction coincides with the longitudinal direction (Z) and is moved in translation along the longitudinal direction (Z) by the control part, in order to displace the movable contact in translation along the longitudinal direction (Z). According to a second embodiment, the transmission insulating part comprises a first section which extends substantially along said longitudinal direction (Z1) from said second end and away from said first end, a curved intermediate section which follows said first section and a second section extending in the longitudinal direction (Z1) from said intermediate section and approaching said first end. According to a third embodiment, said peripheral fin has a quadrangular contour. Preferably, said peripheral fin connects to the body by an intermediate section. Advantageously, the insulating transmission part comprises, at its second end, a connecting part which extends in a direction (Y1) substantially perpendicular to the longitudinal direction (Z1) of the body, said connecting part being provided with an opening tranversante whose contour is of non-circular shape, able to ensure the drive in rotation. Advantageously, the insulating transmission part comprises, at its first end, two substantially parallel protrusions, which extend the body along its longitudinal direction (Z1).

  According to a variant common to the three embodiments, the transmission insulating part comprises an additional peripheral fin. More precisely according to the first embodiment and according to the second embodiment, said additional peripheral fin extends towards said first end substantially in the extension of said first section. Advantageously, said transmission insulating part is arranged in such a way that its longitudinal direction (Z1) coincides with the longitudinal direction (Z) and is set in motion.

  translational movement in the longitudinal direction (Z) by the control member, for moving said movable contact in translation along said longitudinal direction (Z).

  Advantageously, said transmission insulating part is arranged in such a way that its longitudinal direction (Z1) coincides with a transverse direction (X7) perpendicular to the longitudinal direction (Z) and is rotated about said transverse direction ( X7) by the control member to move said movable contact in translation along said longitudinal direction (Z). Finally, said transmission insulating part is arranged in such a way that its longitudinal direction (Z1) coincides with a transverse direction (X10) perpendicular to the longitudinal direction (Z) and is rotated about a transverse direction (Y) perpendicular to said longitudinal direction (Z) and said transverse direction (X10) by the control member to move said moving contact in translation in the longitudinal direction (Z). Furthermore, the invention relates to an electrical switchgear, such as a circuit breaker, a switch, a contactor or a disconnector, characterized in that it is provided with a breaking device according to the present invention. Other features and advantages of the present invention will become apparent upon reading

7

  of the desc_ ~ iption which follows, exemplary embodiment given by way of illustration with reference to the appended figures. In these figures: BRIEF DESCRIPTION OF THE DRAWINGS - Figure 1 shows a longitudinal sectional view of a cut-off device in the closed position according to a first embodiment; Figure 2 is an enlarged portion of Figure 1, centered on the insulating transmission part; Figure 3 is a view similar to Figure 2 but in the open position; Fig. 4 is an enlarged view illustrating the elongation of the spark line; Fig. 5 is a sectional view of an embodiment in which the transmission insulator includes a plurality of fins; Figure 6 shows, in longitudinal sectional view, a cut-off device according to a second variant of the first embodiment; - Figure 7 shows, in longitudinal sectional view, a cut-off device according to a second embodiment; Fig. 8 is a longitudinal sectional view of a cut-off device according to a third embodiment;

  FIG. 9 represents, in perspective view, an insulating transmission part according to the third embodiment of FIG. 8. DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS Referring to FIG. 1, there is shown a cut-off device 100 an electrical switchgear which comprises an insulating transmission part 30 according to a first variant of a first embodiment. The cut-off device 100 comprises a vacuum interrupter 4, part of the envelope of which is made of an insulating material, such as, for example, ceramic material, which has a substantially elongated shape about a longitudinal axis Z. 4 has a first end (upper end in Figure 1), on which is fixed a first connection 6, 20 current conductor and made for example of copper or aluminum. This first conductor 6 is in the form of a block in which is inserted a first socket 8 which exits to the outside of the vacuum bottle 4 and a fixed contact 10 which penetrates inside the housing. 4. Vacuum bulb 4 has a second end (lower end in Figure 1), which opens on a second conductor 12, current conductor and made for example of copper or aluminum. The second conductor 12 is in the form of a tube in which is inserted a second socket 145 which exits the outside of the vacuum bottle 4 and a movable contact 16 which penetrates inside the housing. 4. A flexible electrical connection 18 connects the movable contact 16 to the second socket 14. In the illustrated example, the fixed contact 10 and the movable contact 16 are in contact with each other. at each end of the vacuum bottle 4, along the longitudinal axis Z. The first socket 8 and the second socket 14 are respectively oriented along transverse axes X1 and X2 perpendicular to the longitudinal axis Z and belonging to at the same transverse plane. They are respectively associated with a first plug-in extender 9 and with a second plug-in extension 15. The second tubular-shaped conductor 12 opens on one side on the vacuum bulb 4, and opens, the other side, on an insulating rod of motion transmission. An erosion shield 20 makes it possible to control the electric field applied to the insulating rod. The assembly comprising the vacuum bottle 4, the two conductors 6, 12 and the two plug extensions 9, 15, is surrounded by an overmolded insulating jacket 22 made for example of epoxy resin. In a manner known per se, an intermediate insulating layer 24, making it possible to adapt the expansion coefficient of the vacuum bottle 4 with that of the sheath 22, is disposed between said vacuum bottle 4 and said insulating jacket 22.

  The insulating envelope 22 extends beyond the second conductor 12 along the longitudinal axis Z, forming a cylindrical portion 27 which delimits a well 26, before being fixed by conventional fixing means 29 to a fixed part 28 of switchgear. Inside the well 26 is disposed an insulating transmission part 30. The insulating transmission part 30 is shown on a larger scale in FIG. 2. It comprises a body 32 of substantially elongate and cylindrical shape, extending along a longitudinal axis of the body 32 which, in use, coincides with the longitudinal axis Z. The body 32 has a first end 34 in which is fixed one end of the movable contact 16 which extends along the longitudinal axis Z. It presents a second end 36 in which is fixed a rod 38 which extends along the longitudinal axis Z. In the example illustrated, the movable contact 16 and the rod 38 are respectively screwed into threaded end pieces 40 embedded in the ends 36 of the body 32. The rod 38 carries a plate 42, one of whose faces is in contact with the second end 36 of the body 32. Around the rod 38 are disposed a helical spring 44 and a ring 46, which cooperate in such a manner that the ring 46 can be moved along the rod 38, under the action of a control member 48 to compress the coil spring 44 and thereby to apply a contact force between the fixed and moving contacts of the vacuum bulb, to avoid repulsions

  electromagnetic currents, which would lead to welds between fixed and moving contacts. From the second end 36 of the body 32, the transmission insulating part 30 is extended, at its second end 36, by an end portion 50 comprising: a first section 52 having substantially a bell shape which cap the rod 38 the helical spring 44 and the ring 46, a second section 54 having substantially a peripheral fin 54 which extends towards the first end 34 in a direction substantially parallel to that of the body 32, and - a curved intermediate section 56 which connects the first section 52 and the second section 54. Opposite the end portion 50 of the transmission insulating part 30, the insulating envelope 22 has a shape complementary to the shape of this end portion 50. Indeed, the insulating casing 22 has at this location a peripheral end groove 272 of the cylindrical portion 27, which extends substantially along the longitudinal axis Z. The peripheral end groove 272 is dimensioned such that the second section 54, the end portion 50, can fit noncontactly into this peripheral end groove 272.

  FIG. 3 shows the device that the invention in the open position. In this position, the assembly consisting of the movable contact 16, the insulating part 30, the rod 38, the coil spring 44 and the control part 48 is moved back relative to the position it occupies in FIG.

  The spring 44 relaxes It will be noted in particular that the peripheral fin 54 is partly outside the peripheral groove 272. However, it will be observed that the peripheral fin 54 is not completely disengaged from the peripheral end groove 272. Indeed, the end of the peripheral fin 52 remains engaged in the peripheral end groove, including in the fully extended position of the insulating part 30, corresponding to the open position of the vacuum ampoule. FIG. 4 shows an enlarged view which illustrates how the present invention makes it possible to lengthen the spark line, also called arc distance, despite a relatively shorter length of the part Transmission Insulation 30. The spark line or arc distance is the shortest path of the electric arc in the air. As can be seen in FIG. 4, which shows the device in its open position, the spark line designated by the reference 180 connects the live conductor connected at its end 182 to the ground 184. The spark line passes over the rim 186 of the peripheral end groove 272 and then enters this peripheral end groove passing over the end 188 of the peripheral vane 54. The spark line changes again from direction passing over the end 190 of the dipping flange 23 before being connected to ground. It can thus be seen that the spark line has an accordion fold shape which lengthens its length. Thus, although the overall length of the transmission insulator is reduced relative to the lengths of the prior art transmission insulators, the length of the spark line remains sufficient to prevent the initiation of an arc between the live conductor and mass. It will be observed that the spark line illustrated in FIG. 4 corresponds to the open position of the device of the invention. It goes without saying that it is in this position that the spark line is the shortest. Indeed, it is easy to understand that when the end 188 of the peripheral fin 54 is engaged at the bottom of the peripheral end groove 272, the path to travel in the air to connect the live conductor to the mass is elongated. The position shown in FIG. 4 thus represents the most unfavorable case, and it can be seen that, even in this position, the length of the spark line is significantly longer with respect to the individual spark lines of the insulators. and 30, so that the length of the spark line remains sufficient to prevent the initiation of an arc. The operation of the cutoff device 100 will now be described with reference to FIGS. 1 to 4.

  The control part 48 translates the transmission insulating part 30 in translation along the longitudinal axis Z, which in turn moves in translation along the longitudinal axis Z the movable contact 16 which is fixed on this transmission insulating part 30 its contact with the fixed contact, then presses on the ring 46 which compresses the helical spring 44 against the plate 42 and thus ensures a contact pressure between the fixed and moving contacts of the vacuum interrupter. In the illustrated example, the movements of the moving parts in translation along the longitudinal axis Z are carried out towards the top of the figure to bring the movable contact 16 of the fixed contact 10 and downwards of the figure to move the moving contact away. 16 of the fixed contact 10. During the translational movement of the transmission insulating part 30 to bring the movable contact 16 closer to the fixed contact 10, the second section 54 in the form of a peripheral fin of the end portion 5C 'of the insulating part 30 of the transmission engages in the peripheral end groove 272 of the insulating envelope 22. Thanks to the particular shape of the end portion 50, and in particular thanks to the presence of its second section 54 which forms a peripheral fin , the transmission insulating part 30 may have a significantly shorter length than if it had a conventional shape without peripheral fin. The reduction of the total length of the transmission insulating part contributes to reducing the size of the cut-off device 100 and consequently the size of the switchgear. This reduction in size is further improved, in the example illustrated in Figures 1 and 2, in that the well 26 opens to the fixed part 28 of the switchgear on which is. the insulating envelope 22 is fixed, this fixed part having an opening 280 through which the control part 48 acts on the transmission insulating part 3C. The insulating casing 22 also has a plunging flange 23 which substantially follows the contour of the opening 280 and which protrudes slightly towards the inside of the fixed part 28 in order to allow the spark line to lengthen. FIG. 5 shows a longitudinal sectional view of the shut-off device in the closed position of an alternative embodiment of the device represented in FIGS. 1 to 4. In FIG. 5, the transmission insulating part 30 comprises several peripheral fins. . In the example shown, the transmission insulating part 30 has two peripheral fins. However, one could consider a room that would have three or more peripheral fins. The purpose of these fins is obviously to increase the length of the spark line. Each additional fin lengthens the path from the shortest arc to the air by adding sinuosity to the arc path. ~ n referring to Figure 6, there is shown a switching device 120 of an electrical switchgear which comprises an insulating transmission part according to a second variant of the first embodiment. The elements common to this cut-off device 120 of FIG. 6 and to the cut-off device 100 of FIGS. 1 and 2 bear the same reference numerals. The cut-off device 120 according to the second variant of the first embodiment, shown in FIG. 6, has the following construction characteristics, which are substantially different from those of the first variant of the first embodiment: the fastening of the envelope insulation 22 on a fixed part 28 of the electrical equipment is produced in a transverse direction (transverse axes X3 and X4) of the cut-off device 120 and not in the longitudinal direction (Z axis) thereof, -. the representation of the fixed part 28 is omitted in FIG. 6, the first socket 8 is oriented along the longitudinal axis Z in the extension of the movable contact 10, the representation of socket extensions is omitted. in FIG. 6, the representation of the control part 48 is omitted in FIG. 6, the transmission insulating part 30 has an additional rim 58 which will be described hereinafter.

  Selcn this second variant of the first embodiment, the body 32 of the transmission insulating part 30 has, at its second end 36, an additional flange 58 which extends towards the first end 34, substantially parallel to the second section 54 of the end portion 50, and being substantially in the extension of the first section 52 of the end portion 50. This additional flange 58 forms a peripheral bowl of the body 32 of the transmission insulating part 30, which has the function to lengthen the dielectric path distance of the arc and to collect any metal particles, from the operation of the vacuum bulb, in a dielectrically non-critical area. A third variant, not shown, of the device that cut 100 according to the first embodiment, differs from the first variant, shown in Figures 1 to 4, in that the compression mechanism, comprising the plate 42, the rod 38, the coil spring 44 and the ring 46, is not placed between the control part 48 and the transmission insulating part 30, but between the transmission insulating part 30 and the movable contact 16. 2.5 This third variant is compatible with a transmission insulating part 30 according to the first variant (without additional flange 58) and with the transmission insulating part 30 according to the second variant (with = additional flange 58). The arrangement 30 of the parts according to this third variant is different, but the respective functions of these parts are the same and the overall function of the cut-off device is the same as for the first and second variants. Referring to Figure 7, there is shown a switching device 140 of an electrical switchgear which comprises a transmission insulating part 30 according to a second embodiment. The elements common to this cut-off device 140 of FIG. 7 and to the cut-off devices 100, 120 of FIGS. 1 to 6 bear the same reference numerals. The breaking device 140 according to the second embodiment, shown in FIG. 7, has the following construction characteristics, which may be substantially different from those of the cut-off devices 100, 120 of the first and second variants of the first embodiment: the fixing of the insulating envelope 22 on a fixed part 28 of the electrical equipment is carried out in a transverse direction (transverse axes X5 and X6) of the cut-off device 140 and not in the longitudinal direction (Z axis) of this device; ci, - the representation of the power outlets is omitted in Figure 7, the representation of the extension sockets is omitted in Figure 7, - the fixed contact 10 and the movable contact 30 16 are carried by two conductors respectively 6

  19 12 which are respectively placed at both ends of the vacuum bottle 4, along the longitudinal axis Z, the transmission insulating part 30 has an additional flange 58, similarly to the transmission insulating part 30 according to the second variant of the first embodiment (FIG. 6), the well 26 extends in a transverse direction represented by the transverse axis X7, and not along the Z axis, a contact pressure mechanism, which will be described in FIG. detail below, is placed between the insulating transmission part 30 and the movable contact 16, the action of the control part 48 on the transmission insulating part 30 and the action of the transmission insulating part 30 on the movable contact 16 are different from those of the first embodiment (Figures 1 to 6), and will be described in detail below. The insulating envelope 22 has a cylindrical portion 27 which extends along the transverse axis X7, which is transverse to the longitudinal axis Z. The transmission insulating part 30 is placed in the well 26 and extends along this axis transverse X7. In the illustrated example, the transverse axis X7 is located between the transverse axes X5 and X6, therebetween. The control part 48 is rigidly fixed to the one end 36 of the transmission insulating part 30 and drives the latter in axial rotation around the transverse axis X7.

  For this movement to be possible, the first section 52 and the second section 54 of the end portion 50 of the transmission insulating part 30 have a circular profile centered on the axis X7, and the peripheral end groove 272 also has a circular profile centered on the X7 axis. The shapes and dimensions of the second section 54 and the peripheral end groove 272 of the cylindrical portion 27 are chosen so that a possible movement of the transmission insulating part 30 with respect to the well 26 is an axial rotation around the transverse axis X7. The contact pressure mechanism comprises a pin 38 which extends the end of the movable contact 16 which is external to the empty bulb 4, a helical spring 44 and a ring 46. The coil spring 44 and the ring 46 are arranged around this rod 38, so that the ring 46 is able to compress the helical spring 44 against the movable contact 16 along the longitudinal axis Z The transmission insulating part 30 and the movable contact 16 are not fixed one to the other. A drive mechanism (not shown) connects the first end 34 of the transmission insulating member 30 to the contact pressure mechanism, such that an axial rotation of the transmission insulating member 30 about the transverse axis X7 causes an axial translation along the longitudinal axis Z of the movable contact 16 and the mechanism. The translational movement of the moving contact 16

  along the longitudinal axis Z is guided by guide means, not shown. In FIG. 4, the contact pressure mechanism is shown in solid lines in its position for which the movable contact 16 is in contact with the fixed contact 10, while the dashed lines represent the position of the contact pressure mechanism for which the movable contact 16 is furthest away from the fixed contact 10.

  According to a not shown variant of the second embodiment, the transmission insulating part 30 has no additional flange 58, similarly to the first variant of the first embodiment. Referring to Figure 8, there is shown a switching device 160 of an electrical switchgear which comprises a transmission insulating part 30 according to a third embodiment. The elements common to this cut-off device 160 of FIG. 8 and to the cut-off devices 100, 120, 140 of FIGS. 1 to 7 bear the same reference numerals. The cut-off device 160 according to the third embodiment, shown in FIG. 5, has the following construction features, which may be substantially different from those of the cut-off devices 100, 120, 140 of the first and second embodiments: The fixing of the insulating envelope 22 on a fixed part 28 of the electrical equipment is carried out in a transverse direction (transverse axes X8 and X9) of the breaking device 140 and not in the longitudinal direction (Z axis) of this, - the representation of the power outlets is omitted in Figure 8, - the representation of the extension sockets is omitted in Figure 8, - the fixed contact 10 and the movable contact 16 are carried respectively by two pare 6, 12 which are respectively placed at both ends of the vacuum bottle 4, along the longitudinal axis Z, the well 26 extends in a transverse direction dirty represented by the transverse axis X10, and not along the longitudinal axis Z, a contact pressure mechanism, which will be described in detail below, is placed between the transmission insulating part 30 and the movable contact 16, the transmission insulating part 30 has a shape different from that of the previous embodiments, which will be described in detail hereinafter, - the action of the control part 48 on the transmission insulating part 30 and the action of the insulating transmission part 30 on the movable contact 16 are different from those of the first embodiment (FIGS. 1 to 7), and will be described in detail hereinafter with reference to FIGS. 8 and 9.

  As shown in FIG. 8, the insulating envelope 22 has a cylindrical portion 27 which

  extends along the transverse axis X10, which is transverse to the longitudinal axis Z. The transmission insulating part 30 is placed in the well 26. In the illustrated example, the transverse axis X10 is located between the transverse axes X8 and X9, between these. The transmission part 30 is shown in perspective in FIG. 9. It has a body 32 having a shape substantially elongate about a longitudinal axis Z1, the body 32 being provided with a first end 34 and a second end 36 In the illustrated example, the body 32 has a substantially square or rectangular profile, whose area decreases progressively from its second end 36 towards its first end 34.

  At its second end 36, the body 32 has a connecting portion 360 which extends along a transverse axis Y1 perpendicular to the longitudinal axis Z1. This connecting portion is provided with a through opening 362 whose contour is notched. Around the body 32 and substantially adjacent to the connecting portion 360, the transmission insulating part comprises a peripheral fin 364 which surrounds the body 32 and which extends along the longitudinal axis Z1 towards the first end 34. This peripheral fin has a square or rectangular outline. It is connected to the body 32 by an intermediate section. At its first end 34, the body 32 has two substantially parallel protuberances 366, which extend the body 32 along the longitudinal axis Z1.

  Each of these two protuberances 366 has an end notch 368. The two notches 368 are

  lie facing each other along a transverse axis Y2 parallel to the transverse axis Y1. Returning to FIG. 8, the transmission insulating part 30 is placed in the well 26 in such a way that the two longitudinal axes X10 and Z1 merge and that the two transverse axes Y and Y1 are. confused. A control part 48 acts on the transmission insulating part 30 via a crenellated part 480 engaged in the crenellated opening 362 of the connecting part 360 of the transmission insulating part 30, along the transverse axis Y1 coincides with the transverse axis Y. This control part 48 drives the transmission insulating part 30 in rotation about the Y axis. As a result, the transmission insulating part 30 is movable, in a plane perpendicular to the axis. transverse Y, on either side of a neutral position in which it extends substantially along the transverse axis X10.

  This rotational movement of the transmission insulating part 30 around the transverse axis Y is such that there is no contact between the internal walls of the cylindrical portion 27 surrounding the well 26 and secondly the shape and the dimensions of the peripheral end groove 272 of this cylindrical part 27, which are substantially complementary to those of the first section 52 and the second section 54 of the end portion 50 of the transmission insulating part 30.

  The peripheral end groove 272 of the cylindrical portion 27 has a square or rectangular profile complementary to that of the peripheral fin 364 of the insulating transmission part. Since this profile is not circular, any axial rotation of the transmission insulating part 30 about its longitudinal axis Z1 is prevented. The width of the peripheral end groove 272 is set to allow movement of the transmission insulating member 30 about its neutral position as it is rotated about the Y axis through the control member 48. The contact pressure mechanism comprises a rod 38 which extends the end of the movable contact 16 which is external to the vacuum bottle 4, a helical spring 44 and a ring 46. The coil spring 44 and the ring 46 are arranged around this rod 38, so that the ring 46 is able to compress the coil spring 44 against the movable contact 16 along the longitudinal axis Z. The transmission insulating part 30 and the movable contact 16 do not are not fixed to each other. A second rod 39 extends perpendicular to the rod 38 in a direction parallel to the transverse axis Y. When the transmission insulating part 30 is in place in the well 26, the second rod 39 is positioned in the notches 368 of the insulating transmission part 30, along the axis Y2 thereof. As a result, a rotation or rocking of the transmission insulating part 30 about the transverse axis Y causes a movement of this second rod 39, then

  of the movable contact 16, then of the contact pressure mechanism, in a guided axial translation along the longitudinal axis Z. The translational movement of the movable contact 16 along the longitudinal axis Z is guided by guide means, not represented. In FIG. 5, the first end 34 of the transmission insulating part 30 is represented in solid lines in its position for which the moving contact 16 is in contact with the fixed contact 10, whereas the dotted lines represent the position of the second end for which the movable contact 16 is furthest from the fixed contact 10. In summary, in the foregoing description, three embodiments of a transmission insulating part 30, which is set in motion by a part, have been described. 48 and which moves a movable contact 16 in a switching device 100, 120, 140, 160 of a switchgear. In the first embodiment, the transmission insulating part 30 is driven in an axial translation movement along the longitudinal axis Z, in order to move the moving contact 16 in axial translation along the same longitudinal axis Z.

  In the second embodiment, the transmission insulating part 30 is driven in an axial rotational movement around the transverse axis X7, in order to move the movable contact 16 in axial translation along the longitudinal axis Z.

  In the third embodiment, the transmission insulating part 30 is driven by a

  axial rotation movement about the transverse axis Y, in order to move the moving contact 16 in axial translation along the longitudinal axis Z. The transmission insulating part 30 is made of an electrically insulating material, such as for example thermosetting material such as than epoxy or thermoplastic such as polycarbonate. Of course, the invention is not limited to the embodiments which have just been described, and in particular the transmission insulating part may have variants of shapes and dimensions that allow it to be placed in a different breaking device. which would perform the same functions as those shown.15

Claims (4)

  1. Cut-off device (100, 120, 140, 160) for a high or medium voltage switchgear, such as in particular a circuit breaker, a switch, a contactor or a disconnector, said cutoff device comprising a vacuum interrupter (4) in which are disposed two contacts (10, 16) in a longitudinal direction (Z), at least one of which (16) is movable, said device comprising an insulating envelope which is extended by a cylindrical part (27) which defines a well (26) and an insulating transmission part (30) transmitting a movement between a control part (48) at ground potential and the moving contact (16) under tension, said transmission insulating part (30) comprising a body (32) of substantially elongate shape, a first end (34) connected to said movable contact (16) and a second end (36) connected to said control part (48), characterized in that the transmission insulating part ( 30) has, at its second end (36), one or more peripheral fins (54, 364) extending towards the first end (34) of the transmission part (30) in a longitudinal direction (Z1) of said body ( 32) and in that the fins (54, 364) remain nested in recesses (272) formed in the cylindrical portion (27) which extends the insulating envelope (22) regardless of the position in the movement of the workpiece. order (48) .30   2. Cut-off device according to claim 1, characterized in that the arc distance, namely the path of the electric arc to the shortest in the air, is the shortest in an open position of the cut-off device, wherein the fins (54, 364) remain nested in the recesses (272) formed in the cylindrical portion (27) which extends the insulating envelope (22).   3. Cutoff device (100, 120, 140, 160) according to claim 1 or 2, characterized in that said insulating transmission part (30) is arranged in such a way that its longitudinal direction (Zl) coincides with said direction longitudinal (Z), and in that it is moved in translation along said longitudinal direction (Z) by the control member (48), in order to move said movable contact (16) in translation along said longitudinal direction (Z ).   4. Cut-off device (100, 120, 140, 160) according to one of claims 1 to 3, characterized in that the transmission insulating part comprises a first section (52) which extends substantially in said longitudinal direction ( Z1) from said second end (36) and away from said first end (34), a curved intermediate section (56) following said first section (52) and a second section (54) extending along said longitudinal direction (Z1) from said intermediate section (56) and toward the first end (34). D. Cutoff device (100, 120, 140, 160) according to claim 1 or 2, characterized in that said peripheral fin (364) has a quadrangular contour. 6. Cutoff device (100, 120, 140, 160) according to claim 1, 2 or 5, characterized in that said peripheral fin (364) is connected to the body (32) by an intermediate section (365). 10? Cutoff device (100, 120, 140, 160) according to any one of claims 1, 2, 5 or 6, characterized in that the insulating transmission part comprises, at its second end (36), a part of link (360) extending in a direction (Y1) substantially perpendicular to the longitudinal direction (Z1) of the body (32), said connecting portion (360) being provided with a through opening (362) whose contour is of non-circular shape, adapted to ensure the rotational drive. 8. Cutoff device (100, 120, 140, 160) according to any one of claims 1, 2, 5, 6 or 7, characterized in that the insulating transmission part comprises, at its first end (34) , two protrusions (366) substantially parallel, which extend the body (32) in its longitudinal direction (Zl). 9. Cutoff device (100, 120, 140, 160) according to any one of claims 1 to 8,5 characterized in that the insulating transmission part comprises an additional peripheral fin (58). 10. Cutoff device (100, 120, 160) according to claims 9 and 4, characterized in that said additional peripheral fin (58) extends towards said first end (34) substantially in the extension of said first section (52). ). Switching device (100, 120, 140, 160) according to Claim 1 or 2, characterized in that said transmission insulating part 30 is arranged in such a way that its longitudinal direction (Z1) coincides with a transverse direction ( X7) perpendicular to the longitudinal direction (Z) and in that it is rotated about said transverse direction (X7) by the control member (48) to move said movable contact (16) in translation. along said longitudinal direction (Z). 12. Cutoff device (100, 120, 140, 160) according to claim 1 or 2, characterized in that said insulating transmission part (30) is arranged in such a way that its longitudinal direction (Z1) coincides with a direction cross-section (X10) perpendicular to the longitudinal direction (Z) and in that it is rotated about a transverse direction (Y) perpendicular to said longitudinal direction (Z) and said transverse direction (X10) by the control member 5 (48) for moving said movable contact (16) in translation along said longitudinal direction (Z). 13. Switching electrical equipment, such as a circuit breaker, a switch, a contactor or a disconnector, characterized in that it is provided with a cut-off device according to one of claims 1 to 12. 10