FR2628262A1 - MECHANISM FOR CONTROLLING AN AUXILIARY TRIP BLOCK FOR A MODULAR CIRCUIT BREAKER - Google Patents

Abstract

An auxiliary tripping unit for a modular circuit breaker comprises a tripping relay 18 and a latching plate 24 22 associated with a spring 60 for storing energy. The plate 24 carries a lug 20 for transmitting the tripping order to the circuit breaker switching mechanism, and an articulation pin 28 of a tripping lever, which comprises a first arm cooperating with the latch 32, and a second arm separated from the relay 18 by a reset lever 44 mounted to rotate freely on an axis 46. The relay 18 is used to unlock the latch 32 to release the plate 24, which under the action of relaxation of the spring 60, transmits the tripping force towards the circuit breaker and ensures the automatic reset of the relay 18 by means of the reset lever 44. The relay 18 of the operating mechanism 12 of the auxiliary unit requires a reduced tripping force. Applications: differential release, MX emission and MN undervoltage.

Description

MECHANISM FOR CONTROLLING AN AUXILIARY TRIP BLOCK FOR

MODULAR BREAKER%

  The invention relates to a molded insulated casing auxiliary auxiliary block capable of being attached and coupled laterally to a multipole circuit breaker block comprising at least one pair of separable contacts, and a mechanism for

  switching associated with a main magneto-

  thermal device, the auxiliary unit housing enclosing a control mechanism, which comprises: - a tripping lever controlled by a tripping relay having a control coil and a tripping pin, - a mechanical connection for transmitting the tripping order emitted by the relay pin to the switching mechanism of the circuit breaker block, so as to trigger the latter by cooperation of the coil of said relay, - a catch arranged between a handle and a plate, which is pivotally mounted on a first fixed axis between an armed position and a disarmed position, - an energy accumulator spring biasing the plate towards the disarmed position when the latching caused by the release lever is broken, and an intermediate lever for automatic reset of the relay under the action of the displacement of the plate towards the disarmed position, said lever being articulated on a second fixed axis of the bootmaker. Such a device is known from German Patent 3114717, which is applied to a undervoltage release for a modular circuit breaker. The reset of the relay is performed by the plate acting on the reset lever pivotally mounted on the same axis as the release lever. The coupling of the mechanical tripping link with the circuit-breaker block is effected by means of a bearing fixed on the lower arm of the tripping lever. The plate of the auxiliary block also triggers the switching mechanism of the circuit breaker block, but this tripping is operated with a certain

  delay after unlocking the lock.

  The object of the invention is to reduce the tripping time of the mechanism of a circuit breaker block associated with a

relay of an auxiliary block.

  The auxiliary trigger unit is characterized in that the plate carries a lug of the mechanical trigger connection, and a third axis of articulation of the trigger lever, which comprises a first arm cooperating with the latching, and a second separate arm Relay trigger pin by the reset lever mounted on the second axis. The function of the relay is exclusively to unlock the snap, which then releases the platen. The mechanical energy available following the expansion of the accumulator spring serves simultaneously to transmit the triggering force of the

  circuit breaker block, and to reset the relay.

  After restarting the relay, the mechanical energy is stored again in the accumulator spring of the plate when the lever is actuated to the latching position,

  and the hooking keeps the spring in the armed position.

  The reset lever is equipped with a damping spring on which acts first a projection of the plate during its movement to the disarmed position, the spring being arranged to modulate the resetting force exerted on the relay pin. The damping spring is advantageously shaped as a premounted pin on the reset lever before the setting

  place of the latter in the second axis of the housing.

  A bias spring is associated with the reset lever to bias it against the release lever when the platen is in the armed position. A pre-determined distance then separates the trigger pin from the lever

  reset when the relay is armed.

  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 drawings in which: - Figure 1 is a schematic elevational view of the control mechanism of an auxiliary trigger unit, shown in the engaged position of the circuit breaker; FIGS. 2 and 3 are views identical to FIG. 1, respectively being triggered, and in position

disconnected from the circuit breaker.

  With reference to FIGS. 1 to 3, an auxiliary block 10 for a molded insulated casing 12 may be attached and coupled laterally to a circuit breaker block (not shown).

multipolar conjugate form.

  Each pole of the circuit breaker block is equipped with a switching mechanism, for example of the type described in the French patent application No. 8708037 filed by the applicant on 9/06/1987. The switching mechanism is associated with a manual control swivel lever, and a magneto-thermal main trigger for monitoring the intensity of the current flowing through the blade. A pair of separable contacts cooperates with the switching mechanism to ensure the interruption or closure of the electrical circuit formed between two terminals of

pole connection.

  The triggering auxiliary unit 10 contains a control mechanism 14 controlled by a reset lever 16, and a trip coil relay 18. The mechanism 14 transmits the tripping order from the relay 18 to the circuit breaker block, by

  via a mechanical link 19 trigger.

  This connection is formed by a lug 20 passing through an opening 22 of the housing 12 to cooperate with the trip bar (not shown) of the switching mechanism of the circuit breaker block. The auxiliary unit 10 may be arranged either as a differential trip unit, or as a minimum voltage trip unit MN, or as an emission trigger MX. The control mechanism 14 is standard, while the relay 18 is adapted to each type of trigger. In the case of a differential release, the relay 18 is electrically connected to a differential homopolar transformer residual current detector running through the active conductors input circuit breaker block. During the occurrence of an insulation fault, the differential detector causes the excitation of the relay coil 18 which causes the triggering of the control mechanism 14, and the cascade tripping of the circuit breaker block via the link

mechanical 19.

  In the case of undervoltage undervoltage MN, the relay 18 acts when the voltage of the network to be monitored disappears or reaches a value below a predetermined threshold. This results in an automatic start of the block

circuit breaker on lack of voltage.

  In the case of an MX transmission trigger, the excitation of the relay 18 comes from outside by a remote control circuit controlled by a push button or an automaton. It

  results in remote forced tripping of the breaker block.

  The control mechanism 14 of the auxiliary trigger unit 10 comprises a plate 24 pivotally mounted on a first fixed axis 26 between an armed position (Figure 1) and a disarmed position (Figure 3). The plate 24 carries the lug 20 of the mechanical connection 19 trigger, and a third axis 28 which is threaded a trigger lever 30, the first upper arm cooperates in the locked position with a latching lever 31 to form a latching 32. The latching lever 31 is pivotally mounted limited on an axis 34 of the plate 24, and is coupled to the lever 16 by a transmission rod 36. The reset lever 16 is pivotally mounted on a fixed axis 38 , parallel to the axis 26 of the plate 24, and forms with the rod 36, a toggle joint whose pivot point 40 is eccentric with respect to the axis 38 of the

handle 16.

  The release lever 30 is biased towards the locked position by an elastic tongue 42 acting as a return spring. Between the relay 18 and the plate 24 is arranged an intermediate resetting lever 44 of the relay 18, one of the ends of the lever 44 being mounted for free rotation on a second axis 46. The opposite end 48 cooperates on the left with the pin 50 to actuate the relay 18, and right with the second lower arm of the release lever 30. Between the two ends of the reset lever 44 is a boss 52 on which is preassembled a pin-shaped spring 54. L one of the strands 53 of the hairpin 54 is displaced by a protrusion 56 of the plate 24 when the mechanism 14 is triggered, while the other strand 58 remains permanently in abutment against a protrusion

from the end 48.

  The accumulator spring 60 of the control mechanism 14 is formed by a torsion spring mounted coaxially on the axis 26 of the plate 24. The spring 60 bears on a protrusion 62 of the insulating housing 12, and urges the plate 24 in the direction counterclockwise to the disarmed position (Figure 3), after the failure of the attachment 32 controlled by the stud 50 of the relay 18 trigger. A stop 64 stops the movement of the plate 24 when the lever 16 arrives in the

  circuit breaker opening position (see figure 3).

  The upper edge of the plate 24 is provided with a signaling light 66 that can be positioned opposite a viewing orifice 68 formed in the front face of the boot 12 to signal the tripping of the circuit breaker by the action of the mechanism 14 of the auxiliary block 10. The indicator light 66 advantageously comprises a colored area clearly visible through

the orifice 68.

  The operation of the mechanism 14 for controlling the auxiliary trigger unit is as follows:

CIRCUIT BREAKER

  In the armed position of the auxiliary unit 10, shown in FIG. 1, the lever 16 is in the stable position on the right, and a slight clearance separates the pin 50 from the end 48 of the reset lever 44. The accumulator spring 60 is banded, and the locking of the attachment 32 by the trip lever 30 maintains the kinematic connection between the

platinum 24 and the joystick 16.

  CIRCUIT BREAKER IN TRIP

  In the event of excitation of the relay 18, the trigger pin 50 is propelled in the direction of the arrow F (see FIG. 2), and strikes the reset lever 44 which pivots about the axis 46 in the opposite direction to the Clockwise. The movement of the reset lever 44 drives the release lever 30 from the locked position to the unlocked position so as to break the catch 32, and to break the kinematic connection between the lever 16 and the plate 24. Subject to the action detent of the accumulator spring 60, the plate 24 then pivots about its axis 26 in the counterclockwise direction to the position shown in Figure 3, by fulfilling two distinct functions, namely a first trigger function of the circuit breaker block

  juxtaposed, and a second relay reset function 18.

  The first trigger function is provided by the lug 20 of the plate 24 passing the mechanical connection 19 from the lowered position (Figure 2) to the raised position (Figure 3) along the curvilinear opening 22 of the housing 12. It this results in a tripping of the switching mechanism of the circuit-breaker block, and the automatic opening of the contacts of the

different poles.

  The second reset function of the relay 18 is operated by the engagement of the protrusion 56 with the strand 53 of the spring 54 causing the intermediate reset lever 44 in the direction of clockwise so as to push the pin 50 of inward release (see Figure 3). The relay 18 is reset when the plate 24 comes into contact with the stop 64, and the lever 16 is in the left stable position

  corresponding to the opening position of the circuit breaker block.

  In this position of FIG. 3, the catch 32 is automatically re-locked to restore the kinematic connection between the lever 16 and the plate 24. The damping spring 54 makes it possible to elastically collect the overtravel of the control mechanism 14, and to limit the resetting force on the stud 50 of the relay 18. The accumulator spring 60 remains disarmed as long as the plate 24 is in support

against the stop 64.

  FINAL RESET OF THE AUXILIARY BLOCK.

  The final rearming of the auxiliary block 10 is effected by a rotation of the lever 16 in the direction of clockwise from the left position (Figure 3), to the right position (Figure 1). This movement of the handle 16 returns the plate 24 from the disarmed position to the armed position, during which the accumulator spring 60 is automatically bandaged, and the lug 20 of the trigger link 19 is biased to the lowered inactive position allowing the

closing the circuit breaker.

  The rotation of the handle 16 for the final rearming of the block

  auxiliary 10 can intervene manually or automatically.

  In the first case, the lever 16 is independent of the switching mechanism of the assembled circuit breaker block. In the second case, the handle 16 is connected to the switching mechanism by a

mechanical rearming link.

  Note that the reset lever 44 is provided with a bias spring 70 which urges said lever 44 to bear against the second lower arm of the trip lever 30 when the plate 24 is in the armed position. When the relay 18 is armed, a constant minimum distance separates the pin 50 from the end 48 of the reset lever 44 (see FIG.

figure 1).

  This arrangement makes it possible to reduce the response time of the circuit breaker when transmitting the trip command to

the switching mechanism.

Claims (9)

  An auxiliary molded insulative switchgear (10) which can be coupled and laterally coupled to a multipolar breaker block comprising at least one pair of separable contacts, and a switching mechanism associated with a magneto-thermal main trip unit, the casing (12) of the auxiliary block (10) containing a control mechanism (14), which comprises - a trip lever (30) controlled by a tripping relay (18) having a control coil, and a pin (50) of trigger; a mechanical link (19) for transmitting the tripping order emitted by the relay stub (50) dd (18) to the switching mechanism of the circuit breaker block so as to trigger the latter by cooperation of the coil of said relay (18); ); - a hooking (32) arranged between a handle (1 6) and a plate (24) which is pivotally mounted on a first axis (26) fixed between an armed position and a disarmed position; - A spring (60) energy accumulator biasing the plate (24) to the disarmed position when breaking the attachment (32) caused by the release lever (30); - And an intermediate lever (44) automatic reset relay (18) under the action of the displacement of the plate (24) to the disarmed position, said lever (44) being hinged on a second axis (46) fixed boot (12), characterized in that: the plate (24) carries a lug (20) of the mechanical link (19) tripping, and a third axis (28) of articulation of the tripping lever (30), which comprises a first arm cooperating with the catch (32), and a second arm separated from the relay release stud (50) (18) by the lever of   resetting (44) mounted freely rotatable on the second axis (46).   2. auxiliary tripping unit according to claim 1, characterized in that the reset lever (44) is equipped with a damping spring (54) on which acts first a projection (56) of the plate (24) during its movement towards the disarmed position, the spring (54) being arranged to modulate   the resetting force exerted on the stud (50) of the relay (18).   3. Auxiliary trip unit according to claim 2, characterized in that the damping spring (54) is pre-assembled as a pin on the reset lever (44) before the setting   in place of the latter in the second axis (46) of the housing (12).   4. Auxiliary trip unit according to one of the   Claims 1 to 3, characterized in that the plate (24) is   equipped with a warning light (66) coming opposite a viewing orifice (68) formed in the front face of the casing (12) to signal the triggering of the auxiliary block (10) when the plate (24) is located in the stable position disarmed. 5. Auxiliary trip unit according to one of the   Claims 1 to 4, characterized in that the lever of   resetting (44) is associated with a bias spring (70) urging said lever bearing against the second arm of the trip lever (30) when the plate 24 is in the armed position, and that the pin (50) tripping is separated from the reset lever (44) by a distance   predetermined in the relay's armed position (18).   6. Auxiliary trip unit according to one of   Claims 1 to 5, characterized in that the hooking (32)   comprises a latching lever (31) pivotally mounted limited on a fourth axis (34) of the plate (24), and mechanically coupled to the handle (16) by a rod of transmission (36).   7. Auxiliary trip unit according to one of   Claims 1 to 6, characterized in that the control coil   the polarized relay (18) is connected to a differential current detector. 8. Auxiliary trip unit according to one of the   Claims I to 6, characterized in that the control coil   of the tripping relay (18) is controlled by an external control circuit so as to form a trigger to MX broadcast.   9. Auxiliary trip unit according to one of   Claims 1 to 6, characterized in that the relay (18) of   trigger acts on the control mechanism (14) according to the value of a voltage to be monitored so as to form a   trigger with undervoltage MN.