EP0315093A2 - Electric installation switchgear - Google Patents

Abstract

An electrical circuit breaker with double-contact points (15, 16) corresponding to the number of phases to be switched off, each with two fixed contact pieces (21, 22) and each with a contact link (23), which bridges the two fixed contact pieces (21, 22) and is held in a contact carrier (26), has arc extinguishing devices (17, 18) allocated to each contact point. An impact armature system (33) is allocated to each contact link, and acts via a transmission lever (41) on in each case one contact carrier (26), only for opening it. A latching mechanism (44) is furthermore provided, which is used only for long-term opening of all the contact points (15, 16), and both the impact armature systems (33) and a thermal trip device (47) act on the latching mechanism (44). An electromagnet system (83), which is accommodated in a dedicated housing (80) and has a magnetic armature (84), a magnetic core (82) and a coil (85), is fitted on the sides on the circuit breaker (10), the magnetic armature (84) of which electromagnet system (83) assumes, by means of a restoring spring, only a single quiescent position and, only when it is excited, only a single operating position. The movement of the magnetic armature (84) is transmitted via a drive arrangement (72) to the individual contact points (15, 16), only for switching them off. <IMAGE>

Description

The invention relates to an electrical circuit breaker with the number of phases to be switched off corresponding double contact points, each with two fixed contact pieces and one each bridging, in a contact carrier accommodated contact bridge, with each contact point assigned arc extinguishing devices, each with a contact armature system associated with each contact bridge, via a transmission lever to each a contact carrier only acts to open it, and with a key switch only for permanent opening of all contact points, on which the impact anchor systems and a thermal release act.

In the past, fuses and motor protection switches have been used to protect electric motors, to which a manual or remote-switchable contactor and a thermal overcurrent relay have also been assigned as required. All of these components were individual elements that were connected in series in the supply line to the motor.

Circuit breakers, which offer protection against short circuits and overcurrents, have recently also been used; A contactor has also been provided for switching the motor on and off. An electrical switching device in which the protective function given in the circuit breaker is combined with the switching function given by the contactor has also become known. This switching device with three contact points, which belongs to the type mentioned at the outset, has two electromagnet systems in one housing, one of which is an impact magnet system, which in the event of a short circuit, each contact point individually by striking the respective movable contact piece or its contact carrier and additionally via a switch lock opens all contact points, whereas the other electromagnet system has a contactor like a magnetic core and a magnet armature, which magnet armature acts on all contact piece carriers and thus on all contacts to their opening. The device thus includes a current-limiting circuit breaker function, a contactor function with manual and remote control options, as well as a magnetic-thermal overcurrent relay function against overloads and overcurrents. All of these functions are implemented in components which are "integrally" housed in a housing.

The object of the invention is to provide an electrical circuit breaker of the type mentioned, which is constructed more cost-effectively and is easier to assemble.

This object is achieved in that laterally on the circuit breaker housed in a separate housing, a magnet armature, a magnet core and a coil having an electromagnet system, the magnet armature by means of a return spring occupies only a single rest position and only a single working position when excited, and that a gear arrangement is coupled to the magnet armature, which protrudes from the housing with a transmission element and can be inserted into the circuit breaker and can be directly or indirectly coupled therein to the contact carriers , and which transmits the movement of the magnetic core of the electromagnetic system to the contact carrier for their actuation only in the direction of switch-off.

According to the invention, therefore, an electrical switching device is created, which is an independent basic device in which the contact points, the individual anchoring systems, the thermobimetals and the switching mechanism are located and which thus corresponds to or corresponds to a circuit breaker, and an additional module which is also independent of the basic device, in which an electromagnet system is housed, with which the "protective function" can practically be assigned to the basic device. All actuating components act in the "opening" direction of the contact point, the contact points each being under the pressure of a spring which acts on the contact points in the "closing" direction, and the additional, add-on module has the advantage that it does not have the key switch, but acts directly on the contact points. The configuration according to the invention has the further advantage that the entire device can be manufactured both in the factory and by the user on site, in which the user only has to add the module to the side of the basic device. It is no longer necessary to keep circuit breakers, contactors and a combined "integral" device in stock, but only one circuit breaker and the module.

An advantageous first embodiment of the invention can go that the lever is a double arm lever which is mounted in the housing and one arm of which is coupled to the magnet armature and the other arm of which can be coupled to an actuating bridge element connected to all contact carriers. The double-arm lever can be mounted on a fixed pin in the housing or on an edge of the recess from which it protrudes from the housing.

A further improvement of this embodiment can be found in the characterizing part of claim 4.

An advantageous second embodiment of the invention can go that the transmission arrangement has a shaft as a transmission element which is mounted in the housing and on which a lever which projects with the magnet armature and another lever which projects out of the housing and into the Circuit breaker is insertable, there cooperates with the transmission levers so that the transmission element acts on the transmission lever for actuating the contact bridges only in the opening direction.

It is advantageously provided according to claim 6 that the transmission element designed as a shaft journal can be coupled to the axis of rotation of the transmission lever and is provided with an arm which is connected to the magnet armature, in such a way that the shaft journal only supports the bearing axis of the transmission lever in the opening direction of the Contact bridges operated.

Both configurations result in a simple and quick retrofit by inserting the transmission element into the basic device.

According to the characterizing part of claim 7 is located in the housing to which the basic device can be connected, a switch coupled to its switch lock, which is switched off when the basic device is switched off with the switch lock, so that the supply line to the coil of the electromagnetic system is switched off. This switch can then be switched on again by means of a reset button according to the characterizing parts of claim 8.

Further advantageous refinements and improvements of the invention can be found in the further subclaims.

On the basis of the drawing, in which two exemplary embodiments of the invention are shown, the invention as well as further advantageous improvements and refinements and further advantages are to be explained and described in more detail.

• Fig. 1 Eine Schnittansicht durch das Grundgerät pa­rallel zu der Klemmschraubenverbindungslinie,
• Fig. 2 eine Schnittansicht durch das Installations­schaltgerät in einer Ebene senkrecht dazu, mit angebautem Elektromagnetsystem, in schemati­scher Darstellung,
• Fig. 3 eine weitere Ausgestaltung des anbaubaren Ge­häuses, im Schnitt, ähnlich dem nach Figur 2,
• Fig. 4 eine perspektivische Darstellung des als Wel­lenantrieb ausgebildeten Übertragungselementes und
• Fig. 5 eine Schnittansicht ähnlich der der Figur 1, durch das Grundgerät mit dem Übertragungshebel nach Figur 4.

It shows:

• 1 is a sectional view through the basic device parallel to the clamping screw connection line,
• 2 shows a sectional view through the installation switching device in a plane perpendicular to it, with an attached electromagnet system, in a schematic illustration,
• 3 shows a further embodiment of the attachable housing, in section, similar to that of Figure 2,
• Fig. 4 is a perspective view of the transmission element designed as a shaft drive and
• 5 shows a sectional view similar to that of FIG. 1, through the basic device with the transmission lever according to FIG. 4.

The basic device, which has the reference number 10 in its entirety, is a circuit breaker serving as a motor protection switch, which is accommodated in a housing 11 made of plastic. The housing 11 has an upper housing part 12 and a housing base 13 with a housing base 14. As can be seen from FIG. 1, the contour of the housing 11 is adapted approximately to the contour of a circuit breaker parallel to the connecting line of associated clamping screws.

In the base area 13, the installation switching device has two contact points 15 and 16 per pole and one arc extinguishing device 17 and 18 assigned to contact points 15 and 16, the arc gases of which can be blown off via an outlet opening 19 and 20. The contact points 15 and 16 comprise two fixed contacts 21 and 22, which are bridged with the contact bridge 23 by two movable contact pieces 24 and 25 attached to a contact bridge 23. The contact bridge is inserted in a manner known per se in a contact bridge support 26 made of plastic and is constantly under the force of a contact pressure spring 27 which tries to press all contact pieces in the switched-on position. The two fixed contact pieces 21 and 22 are each attached to an arc guide rail 28 and 29, which arc guide rails 28 and 29 on the one hand run parallel to the arc quenching plate packet 17 and 18 and on the other hand have an area 30 and 31 which are parallel to the direction of movement of the two contact pieces 24 and 25 runs. The coil 32 of an electromagnetic impact anchor system 33 is connected to the section 30 via a line 31, said coil 32 comprising a yoke 34, a magnetic core 35 and has an impact anchor 36; the other end of the coil 32 is connected to a clamping part 37 of a connecting terminal 38, which is accessible via a first opening 39 in the housing 11 for a screwdriver and via a second opening 40, which runs transversely thereto, for connecting a connecting wire. In the area of the clamp 38, a lever 41 is articulated on a pivot 42, which lever 41 lies in the path of movement of the impact anchor 36 and engages with its free end in a recess 43 in the contact carrier 26. If the impact anchor 36 is actuated in the direction of arrow A due to a short circuit, then the lower end of the impact anchor 36 strikes the lever 41 and presses the contact piece carrier 26 and thus the two movable contact pieces 24 and 25 downward into the open position. The upper end of the impact anchor 36 is connected to a switch lock 44 via a line of action 45, which switch lock causes the contact points 15 and 16 to remain open. In the event of a short circuit, the contact points are suddenly opened by the impact anchor 36, whereas, due to a time delay normally associated with the mechanics, the switching lock 44 opens somewhat later and keeps the contact points 15 and 16 open.

A heating element 47 adjoins the area 31 via a strand 46, which is wound around a thermal bimetal 48, which acts on the switching lock 44 via a pin 49 and also permanently opens due to the heating of the switching lock 44. The "other end" of the thermobimetal is connected via a connecting line 50 to a second terminal 51, which is accessible via a hole 52 corresponding to the opening 39 to a screwdriver and via a hole 53 corresponding to the opening 40 to a line connection. The key switch is located in the middle and can be operated manually by a push button 54.

Of course, each double contact point is assigned an impact anchor system and a bimetallic arrangement.

In FIG. 2, the basic device 10 can be seen partly in section, namely transversely to the plane of the drawing in accordance with FIG. 1, and three adjacent poles 60, 61 and 62 can be seen, and a section through the pole 60 can be seen in FIG. The individual poles have the same structure; they each have a contact carrier 26, 63 and 64 with their recesses 43, 65 and 66, in which the lever 41 or corresponding lever engage. The three poles 60, 61 and 62 are separated from one another by intermediate walls 67 and 68 and an actuating bridge 69 is arranged above the contact carriers 26, 63 and 64 and has a recess 70 into which the free, spherically shaped end 71 of a double arm lever 72 engages .

The switching device described above (without said double arm lever) is an independently usable device that takes over the protective function in the event of a short-circuit or overcurrent.

In addition to the motor protection switch or retrofitted to it, there is a housing 80 which carries a magnetic core 82 of an electromagnet system 83 on a support plate 81. As mentioned above, this electromagnet system 83 therefore has the magnetic core and a magnet armature 84 cooperating therewith, both of which, in a manner known per se, have approximately the shape of an E-cut core. A coil 85 is arranged around the middle leg of both the magnetic core 82 and the magnet armature 84 and is wound on a coil former 86 known per se. At the upper end of the magnet armature 84, a magnet armature carrier 87 is attached, which has an extension 88, which extends from the upper end wall 89 of the housing 80 protrudes and carries a nose 90 against which a compression spring 91 is supported; the other end of which is supported against a spring holder 92, so that the extension 88 and thus the magnet armature 84 are continuously acted upon in the direction of lifting off from the magnet core. The other arm of the double lever 72 is articulated on the magnet armature carrier 87 via a pin 93 in an elongated hole 94; the double arm lever 72 is supported in a bearing shaft 95 inside the housing 80.

To the winding 85 of the coil leads 96 and 97 are guided, a switching element 98 being arranged in the feed line 97, which is switched via an action line 99 from the actuating button 54 and thus from the switching mechanism when the contact points of the individual poles are opened, and moreover also switched on via a reset button 100, so that the electromagnetic system 83 can be switched on again or switched to ready for operation.

The switch works as follows:

If the housing 80 with the electromagnet system 83 is not fastened to the switching device 10, then the switching device 10 of FIG. 1 acts like a motor protection switch which contains protection and manual switching functions. In the event of a short-circuit current in one phase or in more phases, the impact armature 36 is actuated so that it actuates the contact carrier 26 or the contact carriers 63 and 64 via the lever 41 or the corresponding levers of the other poles, as a result of which the contact points 15 / 16 can be opened. At the same time - with a certain time delay (see above) - the switch lock 44 is opened over the line of action 45 by the impact anchor 36, so that the position shown in FIG. 1 is final and permanent. The Arcs that form between the two contact pieces 21/24 and 22/25 are extinguished in the arc-quenching plates 17 and 18. If there is an overcurrent, the bimetallic strip 48 is bent out and the switch 44 is also actuated as a result. If, as shown in FIG. 2, the housing 80 is attached to the broad side of the switching device 10, the double-arm lever 72 being introduced through an opening 101 in the broad side wall 102 of the housing 11 and being connected to the actuating bridge 69, then this is practically a contactor emerged, which can either be operated manually - like a normal contactor - or via a remote control via lines A1 and A2. If no current flows through the lines 96 and 97, then the electromagnet 83 does not remain energized and in this way the spring 91 pushes the magnet armature upwards and via the double arm lever 72 and the spherical extension 71 in the pan 70 are the contact points 15 and 16 of the individual poles 60, 61 and 62 opened. When the electromagnet system 83 is energized, the magnet armature 84 is attracted and the double arm lever 71 pivots clockwise, whereby the force of the compression springs 27 is released and the contact points 15 and 16 are closed. In the event of a short circuit or an overcurrent or a switch-off by hand, the switch 98 is also opened at the same time, as a result of which the magnet armature can fall off and the contact points 15 and 16 likewise open via the double arm lever 72. By actuating the reset button 100, the armature cannot be reset, but the current flow to the electromagnet system is closed again.

A further embodiment of the invention is shown in section in FIG. The housing 80 is constructed in the same way as that that in FIG is shown. A double arm lever like that of FIG. 4 is articulated on the magnet armature 84. This double-arm lever, the purely schematic representation of which is shown in FIG. 4, has a shaft 100, at one end of which a lever 101 and at the other end of which a lever 102 is attached, both of which project in the opposite direction and lie in the same plane. The lever 101 has a thickening 103 in which there is an elongated hole 104 which is coupled to a pin 105 on the magnet armature which can slide in the elongated hole 104. The magnet armature has an attachment 87 with a recess 106 into which the lever 101 and, moreover, also one arm of the double arm lever 27 (see FIG. 2) engage. The shaft 100 is mounted in the housing parallel to the longitudinal extension of the laminated sheet-metal cores of the magnetic core 82 or 83 and the magnet armature 84 and the other arm 102 protrudes from the housing, specifically as a transmission element which passes through an opening 107 in the housing of the circuit breaker . Figure 5 protrudes and is coupled to all transmission levers 41 in such a way that the transmission element can only act on the transmission lever in the switch-off direction.

Of course, other configurations of the invention are also possible. For example, a transmission element can protrude from the housing 80, which is directly coupled to the shaft 42 in such a way that it actuates the shaft 42 and thus the transmission lever 41 only in the switch-off direction. It is a kind of one-way clutch.

The reductions brought about by the invention consist primarily in the fact that a motor protection switch can be used to form a motor starter with a contactor-type magnetic drive, so that units which have already been prefabricated and known and used are merely can be supplemented with an additional module to a device with a higher function, namely a contactor with motor protection, and this combination device can be manufactured and retrofitted not only at the factory but also by a customer.

Claims (9)

1.Electrical circuit breaker with the number of phases to be disconnected corresponding to double contact points, each with two fixed contact pieces and one each bridging contact bridge accommodated in a contact carrier, with arc extinguishing devices assigned to each contact point, each with an impact armature system assigned to each contact bridge, which is connected to a contact carrier via a transmission lever acts only on its opening, and with a switching lock only for the permanent opening of all contact points, on which the impact anchor systems and a thermal trigger for tripping act, characterized in that on the side of the circuit breaker (10) housed in its own housing (80), a magnetic armature (84), a magnetic core (82) and a coil (85) having an electromagnetic system (83), the magnetic armature (84) of which, by means of a return spring, assumes only a single rest position and only a single working position when excited , is attachable, and that with the magnet armature (84) a gear arrangement is coupled which protrudes with a transmission element from the housing (80) and can be inserted into the circuit breaker (10) and therein with the contact carriers (26, 63, 64) indirectly or can be directly coupled and which transmits the movement of the magnetic core (82) of the electromagnetic system (83) to the contact carriers (26, 63, 64) for their actuation only in the direction of switch-off. 2. Circuit breaker according to claim 1, characterized in that the lever (92) is a double arm lever which is mounted in the housing (80) and one arm of which is coupled to the magnet armature (84) and the other arm of which can be coupled to an actuating bridge element connected to all contact carriers is. 3. Circuit breaker according to claim 2, characterized in that the double arm lever (72) on a stationary in the housing (80) mounted pin (95) or an edge of the recess from which it protrudes from the housing (80). 4. Circuit breaker according to one of the preceding claims, characterized in that the articulation point on the magnet armature (84) remote end of the double arm lever (72) engages with a thickening (71) in a pan (70) of the actuating bridge (69), so that all three double contact points (16, 17) can be actuated when the magnet armature is actuated. 5. Circuit breaker according to claim 1, characterized in that the transmission arrangement has as a transmission element a shaft which is mounted in the housing and on which a lever which projects with the magnet armature and a further lever which projects as a transmission element from the housing and into the Circuit breaker is insertable, there cooperates with the transmission levers so that the transmission element acts on the transmission levers for actuating the contact bridges only in the opening direction. 6. Circuit breaker according to claim 1, characterized in that the transmission element is a shaft journal rotatably mounted in the housing about its axis, which can be coupled to the axis of rotation of the transmission lever and is provided within the housing with an arm which is connected to the magnet armature, and that the shaft journal can be coupled to the bearing axis of the transmission levers such that the shaft journal actuates the bearing axis of the transmission levers only in the opening direction of the contact bridges. 7. Circuit breaker according to one of the preceding claims, characterized in that in the housing (80) at least one of the feed lines (97, 96) to the coil winding (85) interrupting switch (98) is provided, which can be coupled to the switch lock in such a way, that the switch is also opened when the contact point is triggered and remains open. 8. Circuit breaker according to claim 7, characterized in that the switch (98) inside the housing (80) can be switched on again by means of a reset actuating element (100) guided in the housing. 9. Circuit breaker according to one of the preceding claims, characterized in that in the housing (80) a compression spring (91) is provided, which is connected to the magnet armature (84) extension (88) continuously in the direction "removing the magnet armature from the magnetic core" presses, and that the extension protrudes from the housing, so that the contact points (15, 16) can thus be actuated manually.

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