EP0042778A1 - Single-pole and neutral miniature circuit breaker - Google Patents

Abstract

1. Single-pole and neutral circuit-breaker with narrow and flat parallelepipedic moulded casing (10), comprising : - an operating mechanism disposed with symmetry in the median plane perpendicular to the narrow sides (18, 20, 24, 30) of the casing and taking up the whole width of the casing, said mechanism having an electro-magnetic device (70) of automatic tripping when a short-circuit occurs and a manual handle (22) driving the tipping of a rotating support (78) ; - a set of phase contacts (58, 62) and a set of neutral contacts (48, 50) placed side by side inside said casing, the movable contacts (50, 62) being linked together onto a contact arm (52, 64) mounted in rotation on a common pivot (54) of said rotating support (78), and - an intermediate insulating partition (36) parallel to said median plane and interposed between the phase contacts and neutral contacts, characterized in that the contact zones of the phase contacts (58, 62) and neutral contacts (48, 50) are shifted to realize a manual opening by the handle (22) of the phase contacts before the one of the neutral contacts, and a closing of the neutral contacts before the one of the phase contacts, and in that the electro-magnetic device (70) actuates a drawer (118) bearing on the two contact arms (52, 64) to displace quickly and simultaneously these contact arms in swith-off position when a tripping on short-circuit occurs.

Description

• - un mécanisme de commande disposé symétriquement dans le plan médian perpendiculaire aux faces étroites du boîtier et occupant toute la largeur du boîtier, ledit mécanisme ayant une manette de commande manuelle et un dispositif électromagnétique de déclenchement automatique lors d'un court-circuit,
• - une paire de contacts de phase et une paire de contacts de neutre toutes deux commandées par ledit mécanisme, et logées côte à côte dans ledit boîtier,
• - une cloison isolante intermédiaire parallèle audit plan médian et intercalée entre les contacts de phase et les contacts de neutre.

The invention relates to a single pole circuit breaker and neutral housing molded parallèlépi ^p édique narrow and flat, comprising:

• a control mechanism disposed symmetrically in the median plane perpendicular to the narrow faces of the housing and occupying the entire width of the housing, said mechanism having a manual control lever and an electromagnetic device for automatic triggering during a short circuit,
• - a pair of phase contacts and a pair of neutral contacts both controlled by said mechanism, and housed side by side in said housing,
• - an intermediate insulating partition parallel to said median plane and interposed between the phase contacts and the neutral contacts.

A circuit breaker of the type mentioned is used in terminal distribution installations, in particular in buildings to protect an electrical circuit, and in the open position completely isolate this circuit by cutting both the phase conductor and the neutral conductor. In a known modular system the circuit breaker can be produced by the association of two poles, which are both protected or one of which, the phase pole, is protected, and the other, the neutral pole, is cut. In both cases the number of mobile units is doubled and the size and cost of installation are significantly increased.

The present invention starts from the observation that the cut-off device for the neutral conductor can be simplified, the circuit protection being ensured by the phase cut-off device. The simplification results in particular from the use of the control mechanism of the phase cut-off device for the actuation of the neutral cut-off device, and from the incorporation of the phase and neutral devices in the same housing, the width or pitch is equivalent to that of a single pole.

A circuit breaker of reduced width is already known (French patent? 2,167,302), which comprises two pairs of contacts, isolated from one another for use as a bipolar switch or as a circuit breaker with a protected pole with neutral cut . The pairs of contacts and the associated interrupting chambers are absolutely symmetrical and the contacts open and close simultaneously. When used for a phase and neutral cut-off this device is not optimized.

The present invention aims to remedy the aforementioned drawbacks and the circuit breaker according to the invention is characterized in that said partition is offset laterally relative to said median plane in the areas of extension of the arcs drawn between said contacts to confine with large faces of said housing a first and a second housing chambers respectively of the phase contacts and the neutral contacts, the volume of the first chamber being due to the lateral offset of the partition larger than that of the second chamber.

The control mechanism and the trigger of the protected pole occupy the entire width of the box, only the lower part being subdivided into two chambers to receive the neutral and phase contacts.

When differentiating the neutral and phase contacts, it is important, according to another characteristic of the invention, to open the phase contacts first and to close the neutral contacts first, the contacts opening almost -simultaneously on a short circuit. This avoids any delay in opening detrimental to a quick cut.

According to a development of the invention, the movable phase and neutral contacts are respectively fixed to the ends mites of phase and neutral contact arms made of insulating material and rotatably mounted on a common axis. The delay in opening the neutral contacts is achieved by lengthening the neutral contact arm, inserting additional play between the contact arm and the common control mechanism.

The adjustment of the thermal trip device of the circuit breaker is advantageously carried out by an adjustment screw accessible from the outside of the circuit breaker housing, this screw being screwed into a threaded orifice formed in the plastic wall of the housing. The thread in the plastic material avoids a nut and according to an important improvement of the invention, the threaded orifice opens onto the fixing face of the housing, preferably in the area receiving a removable fixing lock. In the assembled position of the lock, the adjustment screw is camouflaged preventing any modification of the adjustment carried out in the factory.

Each pair of contacts is associated with a breaking chamber with two electrodes or horns for guiding the arc facing each other. A neck or zone of minimum spacing of the electrodes is provided at a location spaced from the contacts in order to avoid any re-priming on the contacts. The switching of the phase arc on the horn is advantageously delayed compared to that of the arc anchored on the neutral contacts, so as not to prematurely switch off the magnetic trip device and the associated extractor.

The two neutral and phase contact arms are mounted on either side of a plate-shaped support of a material molded from an alloy commercially known as Zamak, carrying axes and stops coming from molding. Manufacturing and assembly are thus considerably simplified.

• la figure 1 est une vue en plan d'un disjoncteur selon l'invention;
• la figure 2 est une vue en élévation du disjoncteur selon la figure 1, montrant les contacts de phase en position de fermeture, la cloison latérale du boîtier étant supposée enlevée;
• la figure 3 est une coupe suivant la ligne III-III de la figure 1, la cloison intermédiaire étant supposée enlevée, montrant les contacts de neutre en position de fermeture;
• la figure 4 est une vue de gauche du disjoncteur selon l'invention;
• la figure 5 est une coupe suivant la ligne V-V de la figure 2 ou 3;
• la figure 6 est une coupe suivant la ligne VI-VI de la figure 2 ou 3;
• la figure 7 est une coupe suivant la ligne VII-VII de la figure 2 ou 3;
• la figure 8 est une vue de détail montrant les contacts en cours d'ouverture;
• la figure 9 illustre le schéma électrique du disjoncteur selon l'invention.

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

• Figure 1 is a plan view of a circuit breaker according to the invention;
• Figure 2 is an elevational view of the circuit breaker according to Figure 1, showing the phase contacts in the closed position, the side wall of the housing being assumed removed;
• Figure 3 is a section along line III-III of Figure 1, the intermediate partition being assumed removed, showing the neutral contacts in the closed position;
• Figure 4 is a left view of the circuit breaker according to the invention;
• Figure 5 is a section along line VV of Figure 2 or 3;
• Figure 6 is a section along line VI-VI of Figure 2 or 3;
• Figure 7 is a section along line VII-VII of Figure 2 or 3;
• Figure 8 is a detail view showing the contacts being opened;
• FIG. 9 illustrates the electrical diagram of the circuit breaker according to the invention.

In the figures, a housing 10, made of a mold insulating material, comprises two half-shells 12, 14, assembled by rivets 16. The housing 10 has a generally parallelepiped shape of small width corresponding to a modular system, commercially known as Multi 9 . The housing 10 has a rear face or bottom 18 for attachment to a symmetrical DIN rail and a front face 20 having a passage for a control lever 22. On one of the narrow side faces 24 is arranged a pair of terminals 26 , 28 for supplying the device housed in the housing 10, the opposite face 30 of output carrying a pair of terminals 32, 34, arranged side by side. The width of the housing 10 corresponds to that of a single-pole circuit breaker of the aforementioned modular system and corresponds to two steps of 9 mm, that is to say a width of 18 mm.

The opposite terminals 26, 32 belong to a neutral cut-off circuit, housed inside the housing 10, the terminals 28, 34 belonging to a phase cut-off circuit also housed inside the housing 10. An intermediate partition insulator 36, interposed between the half-shells 12, 14, extends substantially parallel to the large lateral faces of the housing 10 and separates the neutral cut-off circuits and the phase cut-off circuits (see FIG. 6). The intermediate partition 36 has marginal parts 38, 40, which extend in the median plane of the housing 10, parallel to the large lateral faces, being interposed respectively between the neutral and phase terminals 26, 28 and 32, 34. The central part 42 of the intermediate partition 36 is offset laterally relative to the median plane of the housing 10 upwards in FIG. 6, so as to subdivide the part of the housing adjacent to the bottom 18 into two chambers 44, 46 of different thicknesses, the chamber 44 opposite the phase terminals 28, 34 having the greatest thickness. The intermediate partition 36 extends over part of the height of the housing 10 and separates the elements specific to the neutral circuit and to the phase circuit, the common elements, in particular the control mechanism and the trigger described below, being housed in a common part above the partition 36.

Referring more particularly to FIG. 3, which shows the neutral circuit, it can be seen that the supply terminal 26 carries a fixed contact 48, capable of cooperating with a movable neutral contact 50 carried by an insulating contact arm 52 , pivotally mounted on an axis 54. The fixed contact 48 is extended by an arcing horn 49 extending inside the chamber 46 opposite an electrode 51 disposed at the rear of the movable contact 50. The electrode 51 is connected on the one hand to the terminal 32 and on the other hand by a braid 56 to the movable contact 50. The neutral circuit constituted by the terminal 26, the fixed contact 48, the movable contact 50, the braid 56, terminal 32, the arc horn 49 and the electrode 51, is arranged in the space delimited between the intermediate partition 36 and the half-shell 12, in particular in the chamber 46. The arc horn 49 and the electrode 51 diverges from a point or neck 53 of minimum spacing, arranged just behind the movable contact 50 open.

FigJre 2 more particularly illustrates the phase circuit comprising the power supply terminal 28, a fixed contact 58 connected on the one hand to terminal 28 and extended on the other hand by an arcing horn 60, a movable contact 62 , carried by a contact arm 64 made of an insulating material pivotally mounted on the axis 54. The movable phase contact 62 is connected by a braid 66 to the input of a coil 68 of a magnetic trip device, designated by the general reference 70, the output of the coil 68 being connected by a braid 72 to a bimetallic strip 74, connected to the output terminal 34. Opposite the horn 60 and behind the movable contact 62 is an electrode 76 , electrically connected to terminal 34. The part of the phase circuit, consisting of terminal 28, fixed contact 58, horn 60, electrode 76 and terminal 34, is arranged in the space delimited by the intermediate partition 36 and the half-shell 14, in particular in the chamber 44 forming the arc breaking chamber. The horn 60 and the electrode 76 constitute a convergent, divergent whose neck 77 is offset backwards of the chamber 44, relative to the open position of the movable contact 62, to delay the switching of the arc on the electrode 76 and the switching off of the coil 68.

The convergent facilitates the migration of the arc at the start and the neck 77 limits the risks of re-striking on the contacts 58, 62. The permanent current flows through the coil 68 and the bimetallic strip 74 detecting respectively a short-circuit current and a current of overload to cause separation of the contacts 58, 62.

The control mechanism housed in the upper part, in FIGS. 2 and 3, of the housing 10 above the intermediate partition 36 is common to the movable phase contact 62 and to the movable neutral contact 50. The axis 54 of articulation of the contact arms 52, 64 is carried by a plate-shaped support 78, pivotally mounted on a fixed axis 80, secured to the half-shells 12, 14 of the housing 10. Lights 82, formed in the contact arms 52, 64 in line with the passage of the axis 80, allow a limited clearance of the contact arms 52, 64, on the support 78, a spiral spring 84 urging the contact arms 52, 64 in the closed position of the contacts 48 , 50; 58, 62. A spring 86 biases the support 78 in rotation on the axis 80 in the direction of opening of the contacts 48, 50; 58, 62 in the direction of rotation of the needles of a watch in FIG. 2. The support 78 carries a stop 88 capable of cooperating with the ends 90, 91 of the contact arms 52, 64 to drive in rotation towards the position d opening the movable contacts 50, 62. The support 78 cooperates with a drive and locking device comprising an axis 92 capable of struggling in a light 94 in the form of a square formed in the support 78. The axis 92 is formed by the curved end of a rod 96, the opposite end of which is engaged in an orifice 98 in the handle 22, eccentric with respect to the axis of rotation 100. A lock 102, mounted for rotation on a fixed axis 103 , has a stop surface 104 limiting the movement of the axis 92 in the light 94 in the locked position, shown in the figures. The lock 102 cooperates with a latch 106, carried by a latch lever 108, pivotally mounted on a fixed axis 110. The latch lever 108 can be moved to a release position of the latch 102 by pivoting during a deflection of the bimetallic strip 74 or during the attraction by the coil 68 of the core 112 of the magnetic trigger 70. A spiral spring 114 urges the hooking lever 108 and the latch 102 in the locking position shown in the figures. The lever 22 is biased in the open position of the contacts by a spring 116. The support 78 is a molded part, for example made of an alloy commercially known as Zamak, and the pins 54, 80 and stops 88, coming from molding, protrude on either side of the plate, which facilitates mounting.

• En position fermée des contacts 48, 50; 58, 62, le support 78 est maintenu dans la position de fermeture à l'encontre de la force du ressort 86 par l'axe 92 immobilisé d'une part par le verrou 102 empêchant un échappement vers la partie de base de la lumière 94, et d'autre part par le dépassement du point mort de la genouillère, formée par la tige 96 et la manette 22. L'ouverture manuelle des contacts est commandée par un pivotement dans le sens trigonométrique de la manette 22 provoquant une brisure de la genouillère 96, 22 et un déplacement vers le haut sur la figure 2 de l'axe 92, ce déplacement autorisant un pivotement du support 78 dans le sens-des aiguilles d'une montre. Au cours du pivotement du support 78 la butée 88 vient frapper les extrémités 90, 91 des bras de contact 52, 64 pour déplacer les bras de contact en position d'ouverture. Pendant ce mouvement l'axe 92 reste en appui de la surface 104 du verrou 102 et il est facile de comprendre qu'un pivotement inverse de la manette 22 ramène les contacts en position de fermeture, illustrée par les figures. Une ouverture automatique est commandée soit par déflexion du bilame 74, soit par déclenchement électromagnétique par attraction du noyau 112 provoquant le pivotement du levier d'accrochage 108 et la libération du verrou 102. Le pivotement du verrou 102 dans le sens des aiguilles d'une montre sur la figure 2 libère l'axe 92, qui s'engage librement dans la partie de base de la lumière 94 en autorisant un pivotement du support 78 et une ouverture des contacts de la manière décrite ci-dessus. Les ressorts 116 et 114 ramènent automatiquement d'une manière bien connue en soi la manette 22 ainsi que le verrou 102 et le levier d'accrochage 108 en position de verrouillage. La fermeture s'effectue par pivotement dans le sens des aiguilles d'une montre de la manette 22 comme décrit ci-dessus.

The circuit breaker mechanism works as follows:

• In the closed position of contacts 48, 50; 58, 62, the support 78 is held in the closed position against the force of the spring 86 by the pin 92 immobilized on the one hand by the lock 102 preventing an escape towards the base part of the light 94 , and on the other hand by passing the dead center of the toggle joint, formed by the rod 96 and the handle 22. The manual opening of the contacts is controlled by a pivoting in the trigonometric direction of the handle 22 causing a breaking of the toggle joint 96, 22 and an upward movement in FIG. 2 of the axis 92, this movement authorizing pivoting of the support 78 in a clockwise direction. During the pivoting of the support 78, the stop 88 strikes the ends 90, 91 of the contact arms 52, 64 to move the contact arms into the open position. During this movement the axis 92 remains in contact with the surface 104 of the latch 102 and it is easy to understand that a reverse pivoting of the lever 22 brings the contacts back to the closed position, illustrated by the figures. An opening automatic is controlled either by deflection of the bimetallic strip 74, or by electromagnetic triggering by attraction of the core 112 causing the pivoting of the latching lever 108 and the release of the latch 102. The pivoting of the latch 102 clockwise on Figure 2 releases the axis 92, which engages freely in the base portion of the lumen 94 allowing a pivoting of the support 78 and an opening of the contacts as described above. The springs 116 and 114 automatically bring back in a manner well known per se the handle 22 as well as the latch 102 and the latching lever 108 in the locked position. The closure is effected by pivoting clockwise from the handle 22 as described above.

The coil 68 is housed in the common space and occupies the entire width of the housing 10 (see FIG. 7). The core 112 of the coil 68 carries an extractor 118 cooperating with the contact arms 52, 64 to move the contacts 50, 62 to the open position when a short circuit is detected. The neutral contact arm 52 is extended downward in FIG. 3, so as to shift the movable phase 62 and neutral 50 contacts in height (see FIG. 8). This height offset causes a different spacing between the stop 88 of the support 78 and the ends 90, 91 of the contact arms 52, 64, the stop 88 coming during a pivoting in a clockwise direction of the support 78 strike the phase contact arm 64 first to move the latter to the open position. The neutral contact arm 52 is moved with delay when the stop 88 is impacted on the end 90 of the contact arm 52. The extension according to the invention of the neutral contact arm 52 allows the use of the same stop 88 for controlling the opening and a common axis 54 of articulation of the contact arms 52, 64.

During a manual control by the handle 22, the pivoting of the support 78 causes the opening of the contacts of phase 58, 62 before that of the neutral contacts 48, 50 and conversely the closing of the neutral contacts 48, 50 before that of the phase contacts 58, 62. When opening on a short circuit the extractor 118 acts simultaneously on the two movable contacts 50, 62 by immediately creating a double break.

The movable contacts 50, 62 are fixed to the external faces respectively of the contact arms 52 and 64, in order to maximize the insulation spacing of these contacts.

The judicious arrangement according to the invention has made it possible to house the neutral cut-off device and the phase cut-off device in a housing of standard profile and width, corresponding to those of a single-pole circuit breaker. Substitution in an existing installation of a single-pole circuit breaker is therefore facilitated.

Referring more particularly to FIG. 2, it can be seen that the adjustment point of the bimetallic strip 74 is transferred to the face 18 for fixing the housing 10. The adjustment of the bimetallic strip 74 is carried out in a manner well known per se. deformation of its support 120 by screwing or unscrewing an adjustment screw 122 engaged in a threaded orifice formed in the wall of plastic material of the housing 10 and opening onto the fixing face 18. This arrangement has the double advantage of freeing the face narrow lateral 30 for the arrangement of the connection terminals 32, 34, and the transfer of the adjustment point to a face which is not accessible in the fixed position of the housing 10. The tapped orifice advantageously opens into a housing 126 for receiving a locking bolt fixing, not shown, capable of being put in place after assembly of the half-shells 12, 14 and adjustment of the device. The lock engaged in the housing 126 closes the adjustment point and prevents any subsequent adjustment. This arrangement saves the sealing plug and the fixing nut of the adjusting screw 122.

The neutral supply terminal 26 is shifted downward relative to the adjacent phase terminal 28. This height offset allows connection to combs or rectilinear bars respectively of phase and neutral (not shown) connecting a plurality of modules joined by their lateral face and fixed on the same support rail. The offset in height of the terminals 26, 28 corresponds to that of the movable contacts 50, 62, which facilitates the judicious arrangement of the conductors. The output terminals 32, 34, intended to receive output cables, are preferably arranged at the same level, but it would not be departing from the scope of the invention to also shift these output terminals.

Claims (9)

1. Unipolar and neutral circuit breaker with narrow and flat molded parallelepiped housing (10), comprising: - a control mechanism arranged symmetrically in the median plane perpendicular to the narrow faces (18, 20, 24, 30) of the housing and occupying the entire width of the housing, said mechanism having a handle (22) for manual control and an electromagnetic device for automatic triggering during a short circuit, - a pair of phase contacts (58, 62) and a pair of neutral contacts (48, 50) both controlled by said mechanism, and housed side by side in said housing, - an intermediate insulating partition (36) parallel to said median plane and interposed between the phase contacts and the neutral contacts,
characterized in that said partition (36) is offset laterally with respect to said median plane in the areas of extension of the arcs drawn between said contacts to confine with the large faces of said housing a first (44) and a second (46) housing the phase contacts (58, 62) and the neutral contacts (48, 50) respectively, the volume of the first chamber (44) being due to the lateral offset of the partition (36) greater than that of the second room (46). 2. Unipolar and neutral circuit breaker with narrow and flat molded parallelepiped housing (10), comprising: a control mechanism disposed symmetrically in the median plane perpendicular to the narrow faces (18, 20, 24, 30) of the housing and occupying the entire width of the housing, said mechanism having a manual control lever (22) and an electromagnetic device ( 70) automatic triggering during a short circuit, - a pair of phase contacts (58, 62) and a pair of neutral contacts (48, 50), both controlled by said mechanism and housed side by side in said housing, characterized in that the tilting of the lever ( 22) of the closed position towards the open position generates an opening of the phase contacts (58, 62) followed by an opening of the neutral contacts (48, 50), the tilting in the opposite direction causing a closing of the neutral contacts followed closing of the phase contacts and that said electromagnetic device (70) actuates an extractor (118) acting on the mobile phase contact (62) and the mobile neutral contact (50) to accelerate the movement of said mobile contacts by open position when tripped on short circuit. 3. Circuit breaker according to claim 1 or 2, characterized in that the movable phase contact (62) and the movable neutral contact (50). Are each secured to a contact arm (64, 52), said arms of contact being pivotally mounted on a pivot 54 of a common pivoting support (78) capable of being tilted into an open position and a closed position, the contact areas of the phase contacts (58, 62) and neutral contacts (48, 50) being offset for. open the phase contacts before that. neutral contacts and closing the neutral contacts before closing the phase contacts. 4. Circuit breaker according to claim 3, characterized in that the arm (64) of the movable phase contact (62) is shorter than the arm (52) of the movable neutral contact (50). 5. Circuit breaker according to claim 3 or 4, characterized in that the pivoting support (78) is in the form of a molded plate interposed between said contact arms (52, 64) and carrying lateral pivots (54, 80, 88) coming molding. 6. Circuit breaker according to any one of the preceding claims, having a thermal bimetallic trip device (74) and an adjustment screw (122) of the bimetallic strip, characterized in that said screw (122) is screwed into a threaded orifice opening onto a part of the narrow fixing face of the molded case, capped by the fixing lock. 7. Circuit breaker according to any one of the preceding claims, characterized in that a pair of arcing horns (60, 76) is associated with the pair of phase contacts (58, 62) for sensing the arcing and the 'move away from the contact zone, said horns having a neck (77) to avoid any re-priming on the contacts (58, 62). 8. Circuit breaker according to claim 6, characterized in that a pair of arcing horns (49, 51) is associated with the pair of neutral contacts (48, 50) for sensing the arc drawn between the neutral contacts as soon as it forms and move it away from the contact area. 9. Circuit breaker according to claim 7 and 8, characterized in that said arcing horns (60, 76; 49, 51) are shaped so that the switching of the drawn arc between the neutral contacts (48, 50) occurs before switching this the arc drawn between the phase contacts (58, 62).

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