EP0275750A1 - Bipolar differential interrupter with fault indicator - Google Patents

Abstract

The interrupter comprises a control mechanism with handle and differential release (46) comprising a totalising transformer and a release relay (98) cooperating by means of a release rod (142) with the main lock of the mechanism, and with a signalling lock (158) of a fault-indicating lever (152). Automatic resetting of the relay (98) is performed with a resetting lever (144) mounted with limited swivel on the spindle (146) of the indicator lever (152). A projection of the plate for driving the moving contacts causes, during the closing travel of the handle, the displacement of the resetting lever (144) to a neutral position, and the passage of the indicating lever (152) to a passive position. Applications: range of differential interrupters from 25 A to 63 A, and with sensitivities from 10 mA to 500 mA. <IMAGE>

Description

The invention relates to a bipolar differential switch with a molded insulating housing containing:
- a pair of separable contacts per pole in electrical connection with a pair of connection terminals,
a mechanism for controlling the two movable contacts, comprising a lever connected by a mechanical transmission link to a member for driving the movable contacts,
- a spring for actuating the mechanism to cause the opening of the contacts during an automatic tripping on fault,
a differential trip device having a totalizing transformer for detecting a leakage current, and a trip relay intended to cooperate with a main lock of said mechanical connection of the mechanism,
- and an automatic reset device for the relay after tripping.

A known device of the kind mentioned is described in French Patent ^No. 2,530,073 of the applicant. It is a differential trip switch integrated in the same housing. Such an apparatus consists in interrupting an electrical circuit, either manually by the two-position joystick, or automatically in the event of an insulation fault greater than a predetermined threshold. The opening of the switch poles is indicated by the position of the pivoting lever visible from the front face, or by a mechanical indicator fixed to the contacts. This type of signaling is unable to distinguish between manual opening or opening on fault of the switch.

The object according to the invention consists in producing a bipolar differential switch with reduced overall dimensions allowing unequivocal signaling of the differential trip.

The switch according to the invention is characterized in that it further comprises a differential trigger indicating lever cooperating with latching with a signaling lock controlled by the relay, said indicator lever being capable of occupying either an active stable position of signaling of the fault after disengaging the signaling lock by the relay, i.e. a stable inactive position after reclosing the signaling lock operated by manual movement of the lever to the closed position.

The side-by-side arrangement of the trip relay, the differential trip indicator and the control mechanism makes it possible to use a common trip bar, the opposite ends of which cooperate with a main lock of the mechanism, and a signaling lock of the 'indicator.

The device for automatically resetting the relay after tripping occurs by means of a reset lever associated with a return spring. A projection of the movable contact drive member comes into engagement during the closing stroke of the lever with the reset lever to move it against the restoring force of the reset spring towards a neutralization position, authorizing another trigger by the differential trigger.

The automatic reset action of the relay is automatically controlled upon opening by the return spring of the reset lever, while the neutralization of the latter after reset of the relay occurs in the actual position of closing of the movable contacts.

The movable phase and neutral contacts are carried by two insulating support arms secured to a pivoting plate constituting the drive member. The protrusion of the plate causes the closing lever to move from the indicator position from the active position to the inactive position.

According to one embodiment of the invention, the base of the housing serves as a housing for the totalizer transformer and for the contact system and connection terminals, while the cover contains the control mechanism, the differential relay release, and the indicating device differential fault. The internal volume of the base is subdivided by two longitudinal walls and a transverse wall into a plurality of independent compartments comprising:
- the totalizing transformer compartment extending over the entire width of the base, being arranged between the output terminals and the transverse wall,
- two compartments juxtaposed with phase and neutral circuits, located between the input terminals and the transverse wall,
- And a compartment of the test resistance of the test circuit associated with the differential trip device, said compartment being arranged in the width direction between the compartment of the neutral circuit and one of the side faces of the base.

The differential switch is advantageously equipped with a snap-action device.

• - la figure 1 est une vue en élévation de l'interrupteur différentiel bipolaire selon l'invention, représenté en position d'ouverture;
• - la figure 2 est une vue en plan de l'interrupteur selon la figure 1, après enlèvement du capot et du mécanisme de commande à relais de déclenchement;
• - la figure 3 est une coupe selon la ligne III-III de la figure 1;
• - la figure 4 est une vue en élévation du déclencheur différentiel en position armée de l'indicateur et du relais;
• - la figure 5 montre le schéma électrique de l'interrupteur différentiel;
• - la figure 6 représente une vue analogue à la figure 1 d'une variante de réalisation.

Other advantages and characteristics will emerge more clearly from the description which follows of an embodiment given by way of nonlimiting example and represented in the appended drawings in which:

• - Figure 1 is an elevational view of the bipolar differential switch according to the invention, shown in the open position;
• - Figure 2 is a plan view of the switch according to Figure 1, after removal of the cover and the trigger relay control mechanism;
• - Figure 3 is a section along line III-III of Figure 1;
• - Figure 4 is an elevational view of the differential release in the armed position of the indicator and the relay;
• - Figure 5 shows the electrical diagram of the differential switch;
• - Figure 6 shows a view similar to Figure 1 of an alternative embodiment.

In FIGS. 1 to 5, the bipolar differential switch 10 is housed in a parallelepipedal housing 12, of molded insulating material, formed by the assembly of a base 16 and a cover 14 fixed to one another by two fixing screws 18, 20. The differential switch can be connected in a single-phase alternating network with neutral by means of two pairs of terminals 22, 24; 26, 28 for connection, inserted into cells 30 arranged at the four opposite angles of the base 16. The input 24 and output 22 terminals are part of a phase circuit (36) in connection with the phase conductor L , while the input 28 and output 26 terminals belong to a neutral circuit 38 in connection with the neutral conductor N. The two input terminals 24 and 28 are arranged side by side along the narrow face 34 connection, and the two output terminals (22, 26) juxtaposed extend along the opposite narrow face 32 of connection.

The bottom 39 of the base 16 can be snapped onto a symmetrical DIN rail by means of a fixing member 40. The front face of the cover 14 is provided with a passage light for a pivoting control lever 42, and a housing opening a test button 44 to verify the proper functioning of the differential release 46.

The phase circuit 36 comprises a fixed contact 48 fixed on a U-shaped extension of the conductive pad crossing the cage of the input terminal 24, and a movable contact 50 of phase carried by an insulating support arm 52 mounted on an axis 54 articulation secured to a pivoting plate 56. The movable phase contact 50 is connected by a braid 58 to one of the ends of a primary winding 60 comprising one or more turns wound on the O-ring of a differential or totalizing transformer 62. The output terminal 22 is connected at the opposite end of the primary winding 60.

The neutral circuit 38 has a similar structure comprising the input terminal 28 serving to support a fixed contact 64 capable of cooperating with a movable neutral contact 66 carried by an insulating support arm 68, mounted with the support arm 52 adjacent to common axis 54. The movable neutral contact 66 is connected by a conductive braid 70 to the second primary winding 72 of the differential transformer 62, and to the output terminal 26.

The differential transformer 62 and the two circuits 36, 38, of phase and neutral are housed individually in independent compartments 74, 76, 78, respectively subdivided inside the base 16 by insulating walls 80, 82, 84 of seperation.

The two longitudinal internal walls 80, 82 extend in a direction parallel to the large lateral faces 86, 88, opposite the housing to confine in the width direction in addition to the two compartments 74, 76, for housing the circuits 36, 38, phase and neutral, an additional compartment 90 for the installation of the test resistor 92 of the test circuit 94 associated with the differential trip device 46. The compartment 76 of the neutral circuit 38 is interposed between the two compartments 74, 90 of phase circuit 36 and of resistor 92. The two walls 80, 82, are arranged over a fraction of the length of the base 16 up to the zone of meeting with the third transverse intermediate wall 84 extending perpendicularly at the bottom 39 to the separation plane of the base 16 with the cover 14.

The close arrangement inside the base 16 of the differential transformer 62 and of the circuits 36, 38, of phase and neutral between the input terminals 24, 28, and output 22, 26, makes it possible to obtain electrical connections. very short internal parts of the bipolar switch 10. The orifice of the toroid of the differential transformer 62 extends in the longitudinal direction of the poles.

The inside of the cover 14 contains the control mechanism 96, a relay 98 for triggering the differential trip device 46, and a device 100 for indicating a differential fault.

The control mechanism 96 (FIG. 2) is located between two plates 102, 104, above compartment 74 of the phase circuit 36 and compartment 78 of the differential transformer 62, and is common to the two movable contacts 50, 66 of phase and neutral. The axis 54 of articulation of the support arms 52, 68, of the movable contacts 50, 66, is carried by the plate 56 pivotally mounted on a fixed axis 106 secured to one or two plates 102, 104. Lights formed in the support arms 52, 68 in line with the passage of the fixed axis 106 allow a limited clearance of the support arms 52, 68, on the plate 56, a spiral-shaped contact pressure spring 108 urging each arm 52, 68, in the closed position of the contacts 48, 50; 64, 66. A spring 110 for opening the control mechanism 96 is formed by a compression spring inserted between a fixed stop and the plate 56, the latter being biased in rotation on the axis 106 in the opening direction of the contacts. movable, in the direction of rotation of the needles of a watch in FIG. 1. The plate 56 is equipped with a retaining lug 112 intended to cooperate with the ends of the arms supports 52, 68, so as to form a mechanical connection with the movable contacts 50, 66. The plate 56 cooperates with a drive and locking device comprising an axis 114 of transmission capable of struggling in a light 116 formed in the plate 56. The axis 114 is formed by the curved end of a link 118 whose opposite end is articulated to the pivoting lever 42 for manual control, so as to constitute a toggle. A locking hook 120 is mounted for rotation on a fixed axis 122, and on the one hand has a stop surface 124 limiting the movement of the axis 114 in the slot 116 in the locking position shown in FIG. 1, and d 'other hand a hooking spout 126 cooperating with a latch 128 pivotally mounted on a fixed axis 130. A return spring 132 of the spiral type surrounds the axis 122 and biases the latch 128 and the hooking spout 126 in the locked position. The lever 42, mounted with limited pivoting on an axis 134, is biased in the open position (FIG. 1) by a spring 136. The lock 128 can be moved against the restoring force of the spring 132 towards a position release release of the hooking spout 126, during the intervention of the relay 98 of the differential release 46. The hook 120 then pivots clockwise in FIG. 1, and releases the axis 114 from the link 118, causing the mechanical connection between the toggle joint 118, 42 and the plate 56 to break. This results in automatic opening of the contacts 48, 50; 64, 66 by pivoting the plate 56 clockwise under the relaxing action of the spring 110 of the mechanism 96. The lever 42 is moved to the open position by its return spring 136. The spring 132 then participates in the automatic resetting of the lock 128 and of the hook 120, so as to re-establish the mechanical connection between the toggle joint and the plate 56. The manual reclosing of the switch 10 is effected by pivoting clockwise from the lever 42.

With reference to FIG. 4, the relay 98 of the differential release 46 and the fault indicating device 100 differential are arranged on the same side of the plate 104 opposite the control mechanism 96. The relay 98 is of the permanent magnet polarized type, comprising an excitation coil in electrical connection with the secondary winding 140 of the differential transformer 62. The movable pallet of the relay 98 can cooperate (see arrow F 1) with a trip bar 142 capable of actuating the lock 128 towards the triggered position, upon the appearance of a differential fault. An auxiliary lever 144 for resetting the relay 98 is pivotally mounted on an axis 146, and is biased counterclockwise (see arrow F 2) by a resetting spring 148 of the torsion type. The pivoting plate 56 of the control mechanism 96 is equipped with a neutralization projection 150 (see FIG. 1), intended to cooperate with the reset lever 144 during the closing operation by the handle 42, so as to spread the lever 144 of the pallet after resetting of relay 98.

On the same axis 146 of the reset lever 144 is mounted an indicator lever 152 having one end arranged by seeing 154 fault signaling mechanical, and an opposite end carrying a hooking spout 156 cooperating with a signaling latch 158, mounted at limited rotation on an axis 160. A return spring 162 is threaded on the axis 160 and biases the signaling lock 158 in an anti-clockwise direction. The trigger bar 142 serving as a control member between the relay 98 and the main latch 128 of the mechanism 96, also cooperates with the signaling latch 158 of the indicator device 100 during the issuance of a differential trip order by the relay 98.

The classic electrical circuit diagram of the test circuit 94 (see FIG. 5) comprises in series, the resistor 92 for simulating the differential fault, a test switch 166 actuated by the test button 44, and a protection switch 168 automatically opening the test circuit 94 when opening the movable contacts 50, 66, of the switch 10. The connection test circuit 94 is made at a first connection point 170, located between the movable neutral contact 66 and the toroid, and at a second connection point 172 formed between the toroid and the output terminal 22 of the phase circuit 36.

The embodiment of the test circuit 94 illustrated in FIGS. 3 and 4 shows the housing of the test push button 44 in a cavity 174 of the insulating cover 14. A compression return spring 176 is inserted between the test button 44 and the bottom of the cavity 174. The test button 44 carries a pair of contact blades 178, 180, of different lengths, the longest 178 cooperating with a ramp 182 of the movable contact 66 of neutral, and the shortest 180 with a conductor 184 for connection of the resistor 92. It is noted that the blade 178 and the ramp 182 constitute the protective switch 168, and that the blade 180 and the conductor 184 form the test switch 166. The depressing of the push button 44 causes the simultaneous closing of the two switches 166, 168, causing the circulation of an artificial fault current detected by the differential transformer 62. The interruption of the current in the test circuit 94 takes place when the movable neutral contact 66 is opened by spreading the ramp 182 with the blade 178, even if the test button 44 remains in the depressed position.

The operation of the differential trigger mechanism 96 of the bipolar switch 10 is as follows:
- In the closed position (not shown) of the switch 10, the lever 42 is on the right in FIG. 1, and the main lock 128 of the mechanism 96 locks the hooking spout 126 of the hook 120. The spring 110 of opening of the mechanism 96 is compressed to the maximum, and the reset lever 144 of the relay 98 is separated from the pallet by an interval due to the neutralization action of the projection 150 at the upper end of the plate 56. The indicator light signaling 154 occupies an inactive position, and the indicator lever 152 is hooked to signaling latch 158.

During a manual opening command by the lever 42, the pivoting of the plate 56 clockwise causes the opening of the phase 50 and neutral 66 contacts, the main lock 128 remaining in position locked (see Figure 1). The projection 150 of the plate 56 moves away from the reset lever 144, and the spring 148 biases the lever 144 towards the armed position in engagement with the pallet of the relay 98. The indicator lever 152 attached to the signaling latch 158 remains stationary during manual opening of the mechanism 96.

From the closed position, the appearance on the network of a real or artificial insulation fault by the test circuit 94 is detected by the differential transformer which sends a trip order to relay 98 of the differential trip device 46. The movement of the pallet causes the trigger bar 142 to translate to the left (arrow F1 in FIG. 4), causing a combined unlocking movement of the main lock 128 and the signaling lock 158.

This results in the opening of the contacts 48, 50; 64, 66, of the bipolar switch 10 under the action of the spring 110, and a pivoting of the indicator lever 152 in the counterclockwise direction towards an active position for signaling the fault. This position is visible from the outside through a window formed in the front face of the cover 14. During the opening movement of the mechanism 96, automatic resetting of the hook 120 with the main lock 128 takes place, and d on the other hand from the relay 98 by the reset lever 144. The lever 42 occupies the position shown in FIG. 1, and the indicator lever 152 remains permanently in the active fault signaling position.

Manual movement of the lever 42 from the open position to the closed position, ensures the closure of the contacts 48, 50; 64, 66, moves the reset lever 144 of the relay 98 to a neutralization position, and returns the indicator lever 152 to the inactive position. This control of the levers 144, 152 intervenes by the direct action of the projection 150 of the plate 56, the position of which corresponds to the actual position of the movable contacts 50, 66.

The bipolar differential switch 10 can be used in a single-phase network with neutral, or on two phases of a multipolar network. The range covers the ranges from 25 A to 63 A, and the sensitivities of the differential release 46 can range between 10 mA and 500 mA in classes AC and A.

According to the variant of FIG. 6, the bipolar differential switch is equipped with an abrupt engagement device 200 comprising a latching lever 202 mounted with limited pivoting on a fixed axis 204 of the plates 102, 104. The lever latching 202 retains the end of the support arm 52 during a first part of the closing stroke of the lever 42. In a second part of the closing stroke, the pivoting plate 56 acts on a ramp 206 for unlocking the latching lever 202 so as to lift it and release the support arm 52 to ensure the abrupt closure of the movable contact 50 phase. A return spring biases the latching lever 202 towards the holding position of the support arm 52.

Claims (10)

1. Bipolar differential switch with molded insulating housing (12) containing:
- a pair of contacts (48, 50; 64, 66) separable by pole, in electrical connection with a pair of connection terminals (24, 22; 28, 26), - a mechanism (96) for controlling the two movable contacts (50, 66), comprising a lever (42) connected by a mechanical transmission link to a member for driving the movable contacts,
- a spring (110) for actuating the mechanism (96) to cause the opening of the contacts during an automatic tripping on fault,
- a differential trip device (46) having a totalizing transformer (62) for detecting a leakage current, and a trip relay (98) intended to cooperate with a main latch (128) of said mechanical link of the mechanism (96) ,
- And a device for automatically resetting the relay (98) after tripping, characterized in that the switch further comprises an indicator lever (152) for differential tripping cooperating with latching with a signaling latch (158) controlled by the relay ( 98), said indicator lever (152) being capable of occupying either a stable active position for signaling the fault after disengaging the signaling lock (158) by the relay (98), or a stable position inactive after reclosing the signaling lock (158) operated by manual movement of the handle (42) to the closed position. 2. Bipolar differential switch according to claim 1, characterized in that the relay (98) cooperates during the triggering with the main lock (128) of the mechanism (96), and with the signaling lock (158) of the indicator lever (152) via a common trigger bar (142), and that the relay (98 ) is arranged side by side with the control mechanism (96). 3. Bipolar differential switch according to claim 1 or 2, characterized in that the automatic reset device of the relay (98) after tripping occurs by means of a reset lever (144) associated with a return spring (148) and that a projection (150) of the movable contact drive member comes into engagement during the closing stroke of the lever (42), with the reset lever (144) to move it against the force for returning the reset spring (148) to a neutralization position, authorizing another triggering by the differential trigger (46). 4. Bipolar differential switch according to claim 3, characterized in that the reset lever (144) of the relay (98), and the indicator lever (152) of differential trigger are pivotally mounted on a common axis (146), s extending parallel to the axis (160) of pivoting of the signaling lock (158), and that the drive member of the movable contacts (50, 66) is formed by a pivoting plate (56) biased in the direction d opening by the actuating spring (110). 5. Bipolar differential switch according to claim 4, characterized in that the reset lever (144) of the relay (98) is interposed between the plate (56) of the mechanism (96) and the indicator lever (152) of differential triggering, and that the drive towards the neutralization position of the reset lever (144) by the projection (150) of the plate (56), causes simultaneously after triggering the passage of the indicator lever (152) from the active position to the inactive position . 6. Bipolar differential switch according to one of claims 1 to 5, in which the insulating case (12) is formed by an assembly of a cover (14) and a base (16), characterized in that the base (16) serves as a housing for the totalizing transformer (62) and the contact system (48, 50; 64, 66) and connection terminals (24, 22; 28, 26), while the cover (14) encloses the mechanism (96), the differential trip unit (46) with relay (98), and the differential fault indicating device (100). 7. Bipolar differential switch for a single-phase network with neutral according to claim 6, wherein the housing (12) has a parallelepiped shape, characterized in that the input (24, 28) and output (22, 26) terminals are housed two by two in cells (30) arranged at the four opposite angles of the base (16), and that the internal volume of the base (16) is subdivided by two longitudinal walls (80, 82) and a transverse wall (84) in a plurality of independent compartments (74, 76, 78, 90), comprising:
- the compartment (78) of the totalizing transformer (62) extending over the entire width of the base (16) being arranged between the output terminals (22, 26) and the transverse wall (84),
- two compartments (74, 76) juxtaposed with phase (36) and neutral (38) circuits, located between the input terminals (24, 28) and the transverse wall (84),
- And a compartment (90) of the test resistor (92) of the test circuit (94) associated with the differential trip device (46), said compartment (90) being arranged in the width direction between the compartment (76) of the neutral circuit (38) and one of the side faces (88) of the base (16). 8. Bipolar differential switch according to claim 7, characterized in that the summing transformer (62) comprises a toroid-shaped magnetic circuit extending perpendicular to the large lateral faces (86, 88) of the base (16), being arranged under the control mechanism (96) and the trigger relay (98). 9. Bipolar differential switch according to one of claims 1 to 8, comprising a test circuit (94) with push button (44) intended to insert a test resistor (92) to simulate a differential current to test the correct operation of the differential trip device (46), characterized in that the push button (44) of the test circuit (94) is integrated in a cavity (174) of the cover (14) and carries a double test (166) and self-protection switch (168) consisting of two contact blades (178, 180) cooperating respectively with one (66) of the movable contacts of the switch (10), and with a conductor (184) for connecting the test resistor ( 92), the test circuit (94) being automatically put out of service as soon as said movable contact (66) moves from the closed position to the open position, and the two contact blades (178, 180) have different lengths, the longest blade (178) cooperating with a ramp (182) of the movable contact (66 ) neutral. 10. Bipolar differential switch according to one of claims 4 to 9, characterized in that an abrupt latching device (200) comprises a latching lever (202) mounted with limited pivoting on a fixed axis (204), so as to retain the support arm (52) of the movable contact (50) during a first part of the closing stroke of the lever (42), the latching lever (202) having an unlocking ramp on which the plate acts (56) pivoting in a second part of the closing stroke to release the support arm (52), causing the abrupt closure of the movable phase contact (50).

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