FR2778492A1 - Circuit breaker with spring action for resetting contacts - Google Patents

Abstract

The structure provides for rapid resetting after release of circuit breaker contacts.- DETAILED DESCRIPTION - The spring control mechanism for a circuit breaker comprises a shaft (13) connected to an operating mechanism (12) for the switch. This is displaced by the action of a first spring (25), whilst a second spring forces the compression of the first spring. The first spring (25) is compressed after a release operation with the aid of a cable (50) fixed to a pressure disc on the second spring (32) which is displaced by a motor (40). The cable is guided freely through the pressure disc during the compression of the second spring, but is locked when the cable is displaced in the opposite direction

Description

the invention relates to a command for the operation of a switch

  circuits, such as a high-voltage circuit breaker

conventional or armored.

  More specifically, the invention relates to a control comprising springs making it possible to carry out the opening cycles

  and closing times usually requested by users.

  The most commonly requested cycle is a cycle comprising an opening, a closing after 0.3 seconds followed by an opening within 0.02 seconds if the fault has not disappeared. Such

  cycle is generally designated by the abbreviation O-0.3sF-0.02sO.

  We also ask the circuit breaker having carried out a cycle O-

  0.3sF-0.02sO, to be able to close after a maximum delay of 15 seconds, this closing can be followed by an opening in

  a delay of 0.02 seconds if the fault persists.

  From French patent application N 85 15 751, an order is known with rectilinear springs for a high-voltage circuit breaker capable of carrying out the aforementioned cycles. It turned out that the device for resetting the springs of this known control was complex because it included numerous parts and in particular a hook wheel which was subject to rapid wear and which required

frequent replacements.

  From French patent application N 96 04 451, an order is still known with rectilinear springs for a circuit breaker capable of carrying out these opening-closing cycles as indicated above. This control comprises a trigger spring and a coaxial engagement spring, the relaxation of the engagement spring causing compression of the trigger spring. The compression- of the interlocking spring is ensured by an electric motor with two directions of rotation arranged on the axis of the springs and which drives in translation along this axis a rod secured to the arm closing or opening on a support ring for the engagement spring. The support ring of the engagement spring is integral with a movable cylinder, the end of which comprises pivoting fingers provided with shoulders on which a support disc of the trigger spring is supported, these fingers coming into contact. at the end of travel of said cylinder with a fixed cylinder and moving away to release the disc. Such an order has the disadvantage of using a large number of parts and the object of the invention is to propose an order with a system

simpler mechanical.

  To this end, the subject of the invention is a command for a circuit switch, making it possible to carry out a rapid cycle of opening, closing and reopening of the switch comprising a rod connected to an operating rod of I ' switch and movable in translation under the action of the relaxation of a first spring, a second spring whose relaxation causes the compression of the first spring and the compression means of the first spring after a triggering operation, characterized in that the means compression cables comprise a cable, one end of which is fixed to a support disc of the second spring and which is driven in translation in a certain direction of translation by a motor to compress the second spring, this cable being guided freely through a disc d support of the first spring during compression of the second spring and this cable being made integral in

  displacement of the support disc of the first spring by the play of an arc

  abutment of a first plate against the cable when the cable is driven in translation in a direction opposite to said certain direction of translation. The control according to the invention therefore provides mechanical energy to the operating rod of the switch from the energy stored in two springs which are bandaged by the play of the translational movement of a cable or several parallel cables . The compression of the springs by the play of a cable makes it possible to place the motor at the bottom of the pole which contributes to the good compactness of the control. According to a particular embodiment of the control according to the invention, each spring is held in the compressed position by a retractable stop which engages under the spring support disc. To drive the cable in translation, the motor is coupled to a worm screw driving in translation a nut. The cable is made integral in translation with the nut by the play of a bracing of a plate against the cable. This simple arrangement helps to limit

  still the number of pieces of the order.

  The two springs of the control have longitudinal axes which are juxtaposed and the cable is guided between its first end fixed to the support disc of the second spring and the motor by pulleys so as to follow the longitudinal axis of the second spring and l longitudinal axis of the first spring. With this arrangement, a small footprint of the control is obtained depending on the height of the pole, this control being able to be housed inside a box.

  parallelepiped or cylindrical.

  An exemplary embodiment of the control according to the invention is

  described below in detail and illustrated in the drawings.

  Figure 1 is a schematic elevational view partially in section of a circuit breaker pole provided with the control

according to the invention.

  FIG. 2 illustrates the control according to the invention which is in

  a rest position corresponding to the tripped state of the circuit breaker.

  FIG. 3 illustrates the control according to the invention which is in the

  compression position of the engagement spring.

  FIG. 4 illustrates the control according to the invention which is in the

  compression position of the release spring.

  FIG. 5 illustrates the control according to the invention which is in the compression position of the trigger and engagement springs. The example described below relates to a circuit breaker with a pole breaking chamber; of course the control according to the invention can be applied to a circuit breaker or to a disconnector (or other circuit interrupter), whether conventional or shielded, comprising several breaking chambers per pole, for example two T-chambers. In Figure 1, the reference 1 designates an insulating column of a circuit breaker pole. The column rests on a frame 2 fixed to the ground. A fixed contact 3 is placed in the breaking chamber 4

  filled with isolation gas such as sulfur hexafluoride SF6.

  The chamber 4 is delimited, at its upper part, by a first flange 5 to which is fixed a first socket outlet 5A, and, at its lower part, by a second flange 7 to which is fixed a

second outlet 7A.

  The reference 8 designates a fixed blow piston. The movable assembly comprises two contacts 9 and a nozzle 10 integral with a cylinder 11 cooperating with the piston 8. The cylinder is connected to a

  operating rod 12 which passes tightly through the flange 7.

  This rod 12 is connected to a rod 13 forming part of the

  command which has been represented in FIG. 1 by the rectangle 14.

  The control is fixed to the chassis 2 by means that are not

  represented; it is placed directly under the pole to be maneuvered.

  Referring now to FIG. 2, the control according to the invention comprises a metal frame 20, for example parallelepiped, which is rigidly fixed under the column 1 of the

  circuit breaker by conventional means not shown.

  This frame preferably has a closed bottom, not shown. The top of the frame 20 comprises a cover 21 provided with an orifice through which passes the operating rod 13 provided at its end with a disc 26 serving to support a first spring 25, coaxial with the rod 13, and intended to the circuit breaker tripping operation, this spring 25 being subsequently called tripping spring. As will be seen later, this spring 25 is compressed between the cover 21 and the disc 26. The spring 25 is held in a compressed position by at least one retractable rotary stop 27 coming from

  engage under the disc 26 (by recalling a spring 29) when the latter

  it is raised in the direction of the cover 21 and can be operated by an opening coil 28 supplied by devices not shown for operating and / or protecting the

  circuit breaker to be cleared from below the disc 26.

  The control also comprises a second spring 32 which is intended for the switching operation of the circuit breaker. This spring 32 is subsequently called an engagement spring. The spring 32 is mounted on a support disc 33 and is compressed between this disc 33 and the cover 21. In the embodiment of the control according to

  the invention, the spring 32 is placed parallel to the spring 25, that is to say

  say that the longitudinal axes of the springs 32 and 25 are juxtaposed.

  The spring 32 is held in a compressed position by at least one retractable rotary stop 34 (with return spring 36) which engages under the disc 33 when the latter is raised to the cover 21. This stop 34 is operated by through a

  opening coil 35 to be released from below the disc 33.

  The coil 35 can be controlled by the circuit breaker operating and / or protection devices used to control the coil 28. The spring 32 has a force greater than that of the spring 25 to ensure both the latching movement of the circuit breaker and the

spring compression 25.

  As can be seen in FIG. 2, the upper part of the spring 25 engages around a boss 22 of the cover 21 while the lower part of the spring 25 fits into a ring 24 of the disc 25 which contributes to the good maintenance axial of the spring 25 when it is compressed or relaxed. Furthermore, the upper part of the spring 32 engages in a crown 23 formed in the cover 21 while the lower part of the spring 32 engages in another crown 37 of the disc 33 which contributes to the good maintenance

  axial of the spring 32 when it is compressed or relaxed.

  The control also comprises an electric motor 40 with two directions of rotation which is fixed for example to a support plate 45 which is itself fixed to the frame 20 under the discs 26 and 33. The electric motor drives in translation a cable 50, one end of which is fixed to the disc 33. In the embodiment shown in the figures, the control uses a single cable which extends substantially along the axis of each spring 32 and 25 but it is possible, for example, to provide two parallel cables ( or more) which extend along the springs 32 and 25. This cable is guided to follow a path passing along the spring 32, then along the spring 25 and ending on a straight portion where it is engaged with the motor 40. More particularly, the cable 50 is fixed on a central protuberance of the disc 33. It then extends substantially vertically along the axis of the spring 32, passes through the cover 21, is returned in a horizontal direction tale by a first pulley 60 mounted on top of the cover 21, is returned substantially vertically by a second pulley 61 mounted on the top of the cover 21, again crosses the cover 21 to extend along the rod 13 surrounded by the spring 25. It is then guided by a third pulley 62 fixed to the rod 13 to cross perpendicularly and substantially centrally the disc 26 then the plate 45. Finally it is returned horizontally by a pulley 63 for example fixed to the plate 45 where it ends with its straight section. It should be noted that the rectilinear section for terminating the cable 50 can equally well be arranged vertically if such an arrangement promotes a reduction in

  the size of the control under the pole.

  The disc 26 has a recess on its underside in which is mounted a rotary plate or washer 70 which is traversed by the cable 50. This preferably rectangular plate 70 is mounted to rotate about a central axis 71 so that when 'It is positioned perpendicular to the cable 50, the latter slides freely through the plate and when it is positioned obliquely with respect to the cable, it bends against the latter and remains engaged therewith. This plate 70 is braced against the cable by a lug 72 which passes through the plate 45 and which pushes one end of the plate 70 under the action of a constrained spring 73. Another lug 74 is provided for passing through the disc d 'support 26 so as to act on the plate 70 to position it

perpendicular to the cable 50.

  Finally, the motor 40 is coupled to an endless screw 41 on which is mounted a nut 4. Another plate or washer 43 rotatably mounted around an axis 45 in a recess of the nut 42 and

  crossed by the cable 50 comes to be blocked by the play of an arc

  buttoning on the cable 50 when it is disposed obliquely with respect to the latter while it lets this cable 50 spin freely when it is positioned perpendicularly to the latter. The end

  free of cable 50 is held taut by means of a spring 80.

  The operation of the control according to the invention is as follows. Figure 2, the control occupies a rest position. The springs 25 and 32 are relaxed. The support discs 26 and 33 rest on the plate 45. The nut 42 is positioned along the screw

  endless 41 in order to be able to move the cable 50 in translation.

  When the circuit breaker is in normal operation, that is to say in the engaged position, the two springs 25 and 32 are held

  bandaged by retractable stops 27 and 34.

  To band the engagement spring 32 as shown in FIG. 3 from the rest position of the control, the motor 40 is started to drive the worm 41 so as to move the nut 42 to the left in FIG. 2. In this direction of movement of the nut 42, the plate 43 is placed obliquely relative to the terminal rectilinear portion of the cable 50 and is bent over this cable to cause it to move in accordance with the direction indicated by the arrow C. The cable pulls the support disc 33 which approaches the plate 21 so that the spring 32 is compressed. When the support disc 33 crosses the retractable stop 34, the latter engages under the support disc to keep the spring 32 bandaged. Note that the cable 50 passes freely through the plate 70 when it is moved in translation in the direction indicated by the arrow C since the

  plate 70 is naturally placed perpendicular to the cable 50.

  Once the retractable stop 34 is engaged under the support disc 33, the direction of rotation of the motor 40 is reversed to return the nut 42 to the right end of the worm 41 in FIG. plate 43 is forced to return in a position perpendicular to the cable 50 and therefore slides along the latter. To note

  that the cable 50 is kept taut by the action of the spring 80.

  To band the trigger spring 25 by the rebound of the spring 32, it suffices to feed the reel 34 to cause the rotary stop 34 to retract from the underside of the support disc 33. By relaxing, the spring 32 moves the support disc 33 which drives the cable 50 in the direction indicated by the arrow D. By the play of the bracing of the plate 70 on the cable 50, the support disc 26 is made integral in displacement of the cable 50 which causes the displacement of the support disc 26 towards the plate 21 and therefore the compression of the spring 25 as visible in FIG. 4. At the same time, the rod 13 is moved so that the circuit breaker is engaged. When the support disc 26 crosses the retractable stop 27, the latter engages under the support disc 26 to keep the spring 25 bandaged. Note that during this

  operation, the cable 50 moves freely through the plate 43.

  In the banded position of the spring 25, the rotary plate 70 is held substantially perpendicular to the cable 50 by the play of

  the lug 74 which penetrates through the support disc 26.

  At this stage, the command is ready to ensure a quick operation of tripping of the circuit breaker by simply actuating the coil 28 to release the retractable stop 27 from below the support disc 26. While moving, the support disc drives the rod 13 to trip the circuit breaker. Once the coil 28 is actuated, the control returns to the position shown in Figure 2 and the trigger spring 25 can again be bandaged as

indicated above.

  The control can also be positioned so that the two springs 25 and 32 are bandaged simultaneously so that they can

ensure an O-F-O sequence.

  In this case, from the state of the command shown in FIG. 4, the engagement spring 32 is again bandaged by commanding

  the motor 40 for moving the nut 42 to the left in FIG. 4.

  The cable 50 therefore pulls the support disc 33 towards the plate 21 which compresses the spring 32. The retractable stop 34 engages under the support disc 33 and the trigger spring is thus kept compressed. The control is then placed in the position shown in Figure 5. The direction of rotation of the motor 40 is then reversed to return the nut 42 to the right of the worm 41 in the figure

5.

  To carry out the O-F-S sequence, the coil 28 is first actuated and the retractable stop 27 emerges from below the support disc 26. The spring 25 relaxes and drives the rod 13 which drives

  the operating rod 12 of the circuit breaker. The circuit breaker is open.

  The coil 35 is then actuated and the retractable stop 34 emerges from below the support disc 33. The spring 32 relaxes and drives the cable 50 in the direction indicated by the arrow D. The spring is then compressed and the rod 13 is moved to trip the circuit breaker. The spring 25 is held in a position compressed by the retractable stop 27. This retractable stop 27 is then actuated to trip the circuit breaker. At the end of this O-F-O sequence, the control is found in the position shown

figure 2.

Claims (4)

  1 / A command for a circuit switch, making it possible to carry out a rapid cycle of opening, closing and reopening of the switch (OFO cycle), said command comprising a rod (13) connected to an operating rod ( 12) of the switch and displaceable in translation under the action of the relaxation of a first spring (25), a second spring (32) whose relaxation causes the compression of the first spring (25) and means of compression of the first spring (25) after a triggering operation, characterized in that the compression means comprise a cable (50), one end of which is fixed to a bearing disc (33) of the second spring (32) and which is driven in translation in a certain direction of translation by a motor (40) to compress the second spring (32), this cable being guided freely through a bearing disc (26) of the first spring during compression of the second spring and this cable being made united in unfolding acement of the support disc (26) of the first spring by the play of a bracing of a first plate (70) against the cable when the cable is driven in   translation in a direction opposite to said certain direction of translation.   2 / The control according to claim 1, wherein each spring (25,32) is held in the compressed position by a retractable stop (27, 34) which engages under the support disc (26.33) of the spring.   3 / The control according to claim 1, in which the motor (40) is coupled to a worm (41) driving in translation a nut (42), the cable (50) being made integral in translation with the nut by the play of a bracing of a second plate (43) against the cable when the nut is moved in translation in said certain direction of translation. 4 / The control according to claim 1, wherein said first plate (70) is rotatably mounted in a recess of said   support disc (26) of the first spring (25).   / The control according to claim 3, wherein said second plate (43) is rotatably mounted in a recess of The nut (42).   6 / The command according to one of claims 1 to 5, in which   the two springs (25,32) have longitudinal axes which are juxtaposed and in which said cable (50) is guided between its first end fixed to the support disc of the second spring (32) and the motor (50) by pulleys so as to follow the longitudinal axis of the second   spring and the longitudinal axis of the first spring.