EP2019406A1

EP2019406A1 - Fixing device for a circuit breaker

Info

Publication number: EP2019406A1
Application number: EP07425462A
Authority: EP
Inventors: Roberto Boffelli; Ivano Mostosi
Original assignee: BTicino SpA
Current assignee: BTicino SpA
Priority date: 2007-07-25
Filing date: 2007-07-25
Publication date: 2009-01-28
Anticipated expiration: 2027-07-25
Also published as: PL2019406T3; EP2019406B1; DE602007006787D1; ATE469433T1; ES2346480T3

Abstract

A fixing device (4) for circuit breakers (8), in particular for moulded case electrical circuit breakers, a base for circuit breakers and a circuit breaker group. The fixing device allows both the removal and the extraction of the circuit breaker so as to run operating tests of the circuit breaker without the need of having to arrange the circuit breaker on makeshift surfaces and without using extension cables of various types.

Description

The present invention relates to a fixing device for circuit breakers, and in particular moulded case electrical circuit breakers, a base for circuit breakers and a circuit breaker group.
To mechanically fix a moulded case circuit breaker in the inner space of an electrical panel and ensure the electrical connection of such circuit breaker to an electrical installation, it is known to use a support and electrical connection base. Such base is typically mechanically fixed to the electrical panel, for example to a vertical plate or to uprights/crosspieces seated in the inner space of the electrical panel, and moreover it is electrically connected inside the electrical panel to an electrical installation the circuit breaker is to be connected to and in particular, to an electrical circuit upstream of the circuit breaker, or line circuit, and an electrical circuit downstream of the circuit breaker, or loading circuit.
The base includes electrical connection terminals, for example in the form of terminals, suitable for cooperating with respective connection terminals of the circuit breaker for connecting the circuit breaker to the line circuit and to the loading circuit. The connection terminals of the circuit breaker are for example made in the form of bars intended for being coupled into corresponding complementary terminals provided in the base.
The use of a support and electrical connection base inside an electrical panel allows making the removal of the circuit breaker from the electrical panel and optionally a subsequent re-installation especially easy and quick. The removal of a circuit breaker becomes necessary for example if the circuit breaker installed in the panel must be replaced with a new one or when, as required by the safety regulations, the temporary removal of the circuit breaker and its separation therefrom are required for carrying out maintenance operations on the electrical system controlled by the circuit breaker.
There is often the need of disconnecting the circuit breaker from the base, and in particular from the line circuit and from the loading circuit for running an operating test with cut off system of auxiliary functions of the circuit breaker. By auxiliary functions it is meant functions of various types, such as signalling, motor, etc. not directly related to the main function of the circuit breaker, that is, that of electrically connecting/disconnecting the line circuit from the loading circuit.
To carry out such test, in known devices, following the complete removal of the base, the circuit breaker is usually arranged on makeshift surfaces in the proximity of the electrical panel housing the circuit breaker and temporary electrical connections are made, for example by extension cables, between auxiliary connection terminals of the circuit breaker and the electrical panel or the base. By auxiliary connection terminals of the circuit breaker it is meant low voltage connection terminals distinct from the power connection terminals, that is, distinct from the terminals needed to connect the circuit breaker to the electrical line and loading circuit. The operation for removing the circuit breakers is quite difficult since the switches could weigh more that few kilos; moreover, it is necessary to provide for a support table for the removed circuit breakers as well as a plurality of electrical connection extensions for running the various tests. Moreover, there is the risk for the operators to accidentally touch live parts, such as the same parts of the base that are visible after the removal of the circuit breaker.
The object of the present invention is to solve the disadvantages mentioned with reference to the prior art.
Such disadvantages and restrictions are solved by a fixing device for circuit breakers in accordance with claim 1.
Other embodiments of the device according to the invention are described in the subsequent claims.
Further features and the advantages of the present invention will appear more clearly from the following description of preferred non-limiting embodiments thereof, wherein:
figure 1 shows a perspective view of a fixing device for circuit breakers according to the present invention;
figure 2 shows a perspective view of the fixing device of figure 1, according to a different angle;
figure 3 shows a perspective view of a circuit breaker provided with the fixing device of figure 1;
figure 4 shows a perspective view of a base for circuit breakers according to the present invention;
figure 5 shows a front view of the enlarged detail VII of figure 4;
figure 6 shows a side partial section view of a circuit breaker group according to the present invention, in a configuration of insertion of the circuit breaker;
figure 7 shows a side partial section view of a circuit breaker group according to the present invention, in a configuration of removal of the circuit breaker;
figure 8 shows a side partial section view of a circuit breaker group according to the present invention, in a configuration of removal of the circuit breaker.
In the different figures, like or similar elements shall be indicated by the same reference numerals.
With reference to the above figures, reference numeral 4 globally denotes a fixing device for a moulded case circuit breaker 8 suitable for being associated to a support and electrical connection base 12.
Base 12 can be used for mechanically fixing the moulded case circuit breaker 8 into the housing of an electrical panel and for securing the electrical connections of circuit breaker 8 to an electrical circuit upstream of base 12 and to an electrical circuit downstream of base 12. The electrical circuits upstream and downstream of base 12 are generally respectively indicated with "line circuit" and "loading circuit".
A moulded case circuit breaker, as opposed to a so-called "open-type" circuit breaker, comprises a box shaped body 16 made of insulating material, which has a carrying function for the internal circuits and mechanisms of the circuit breaker. At present, moulded case circuit breakers are generally used in the fields of industrial automation and of the high-tech service industry for cutting off currents for example even having a value up to 1500 A.
The moulded case circuit breaker 8 for example is a magneto-thermal switch. More in detail, in the particular example described circuit breaker 8 is a tripolar magneto-thermal moulded case circuit breaker.
The box-shaped body 16 of circuit breaker 8 comprises a back face 18, directly opposite the associable base 12 and a front face 19, opposite the back face 18 and carrying a control lever 20.
Circuit breaker 8 can advantageously be provided with gripping handles 22, connectable to two opposite horizontal faces 24 of the box shaped body 16 of circuit breaker 8 and suitable for making the connecting/disconnecting operations between circuit breaker 8 and base 12 easy and comfortable.
As can be seen in figure 3, circuit breaker 8 comprises two opposite arrays of electrical connection terminals 27, 28, or power terminals 27, 28, for the electrical connection of circuit breaker 8 to the relative electrical panel, and in particular to the line circuit and to the loading circuit by the associable base 12. The electrical connection between circuit breaker 8 and base 12 takes place following the complete insertion of circuit breaker 8 into the relative base 12 (figure 6).
Base 12, shown in figure 4, comprises a base body 32 of electrically insulating material with essentially parallelepiped shape, having a front face 36 intended for being juxtaposed to the back face 18 of the box shaped body 16 of the moulded case circuit breaker 8.
Base 12 is provided with a first array of connection terminals 15, 15', or input terminals, suitable for allowing the connection of base 12 to the line circuit inside an electrical panel. For example, the connection terminals 15, 15' include screw terminals connectable to repartition bars housed in an electrical panel.
Base 12 is further provided with a second array of connection terminals 17, 17' or output terminals, suitable for allowing the connection of base 12 to the loading circuit inside an electrical panel. For example, the connection terminals 17, 17' include screw terminals connectable to repartition bars housed in an electrical panel. The base is set up so as to be connected to three-phase line and loading circuits using only the input 15 and output terminals 17 and as to be connected to a three-phase line/loading circuit plus neutral using the additional output terminals 15', 17'.
Base 12 further comprises two further arrays 37 and 38 of connection terminals suitable for cooperating, when the circuit breaker is fully inserted in the base, respectively with the power terminals 27, 28 of the circuit breaker for electrically connecting circuit breaker 8 to the electrical line circuit and to the electrical loading circuit. As is well known to an expert of the circuit breaker, the function of circuit breaker 8 is to selectively enable/cut off the electrical connection between the line circuit and the loading one.
As can be seen in figure 4, in the example described base 12, non-limitingly, includes two further connection terminals 37', 38', since it is set up also for being associated, as an alternative to the tripolar circuit breaker 8, also to a quadripole circuit breaker.
The electrical connection terminals 37, 38 of the base for example are clamp terminals suitable for receiving complementary power terminals 27, 28 of the associable circuit breaker 8.
Base 12 is further provided with means, not shown in the figures, suitable for allowing the mechanical fixing thereof in the inner space of an electrical panel. For example, such fixing means are arrays of holes or notches suitable for allowing, by screws or bolts or similar or equivalent removable coupling means, the coupling of the base to a vertical plate or to uprights/crosspieces housed in the inner space of an electrical panel.
Base 12 comprises retaining means 40, visible in figure 5, suitable for making a mechanical coupling, preferably a shape coupling, with the associable circuit breaker 8 and an insertion seat 42 for the electrical circuit breaker 8 suitable for seating at least partly the box shaped body 16 of circuit breaker 8.
Advantageously, the retaining means 40 are suitable for selectively constraining circuit breaker 8 to base 12 in an insertion position and in a removal position of the circuit breaker. In the insertion position, circuit breaker 8 is inserted in base 12, mechanically connected thereto and with its power terminals 27, 28 electrically connected to complementary terminals 37, 38 of the base. In the removal position circuit breaker 8 is mechanically constrained to base 12, but in such position the electrical power terminals 27, 28 of the circuit breaker are electrically insulated from the complementary connection terminals 37, 38 of the base.
According to an embodiment, the retaining means 40 comprise at least one pair of retaining bars 44 that form a meatus 46 suitable for seating corresponding coupling means 48 of the fixing device 4 of the associable circuit breaker 8.
According to an embodiment, bars 44 are offset relative to an axial direction so as to determine a meatus 46 having such axial extension as to seat, in the removal configuration, the coupling means 48 of the fixing device 4. By axial direction it is meant a direction parallel to the insertion direction of the circuit breaker in the relative base 12.
According to an embodiment, bars 44 are offset relative to a vertical direction, perpendicular to said axial direction, so as to determine a meatus 46 having such vertical extension as to seat, in the removal configuration, the corresponding coupling means 48 of the fixing device 4.
Preferably, the retaining means 40 comprise two pairs of bars 44 each forming a meatus 46 suitable for seating the coupling means 48 of the fixing device 4.
Preferably, base 12 comprises at least one centring element 78 suitable for receiving corresponding insertion guides 98 of the fixing device 4 so as to ensure the centring of circuit breaker 8 relative to base 12.
The fixing device 4 is associated to the back face 18 of the box shaped body 16 of circuit breaker 8, so that in an assembled configuration of the circuit breaker group, the fixing device 4 is arranged between the electrical circuit breaker 8 and the relative insertion base 12.
Advantageously, the fixing device 4 comprises coupling means 48 to base 12 and actuating means 64 of said coupling means 48 suitable for locking and releasing the coupling means 48.
Advantageously, the coupling means 48 are suitable for selectively constraining circuit breaker 8 to the relative base 12 in an insertion position and in a removal position of the circuit breaker 8.
In the insertion position, circuit breaker 12 is mechanically connected to base 12 and the power terminals 27, 28 are electrically connected to the terminals of base 12; in the removal position, circuit breaker 8 is mechanically constrained to base 12 and to the power terminals 27, 28 electrically insulated from base 12. As is known by a man skilled in the art, in the insertion position it is possible to lock the circuit breaker to base 12 by removable fixing means such as hooks, screws and the like, in se known by a man skilled in the art and thus not further described herein.
According to an embodiment of the present invention, the coupling means 48 comprise at least one jaw 68' suitable for making a shape coupling with the retaining means 40 of the associable insertion base 12.
According to an embodiment, said at least one jaw 68 is hinged about at least one fixed pin 72, arranged at the back face 18 of the associable circuit breaker 8, so as to directly face the retaining means 40 of base 12.
Preferably, the coupling means 48 comprise a pair of jaws 68', 68" suitable for making a shape coupling with the retaining means 40 of the associable insertion base 12.
According to a preferred embodiment, jaws 68 are mechanically hinged to each other so that the relative opening/closing movement of the two jaws is synchronised.
According to an embodiment, one of said jaws 68' comprises a pin 74 and the other one of said jaws 68" comprises a fork portion 76 suitable for fitting on said pin 74, so as to obtain an axially moving hinge.
Preferably, jaw 68', 68" comprises a hook end 80 suitable for locking on the retaining means 40, and in particular on bars 44 of the associable insertion base 12.
Preferably, the hook end 80 comprises a chamfer or inclined surface 82 directly facing the associable base 12 and suitable for opposing the insertion of circuit breaker into the relative base 12.
The actuating means 64 comprise at least one transmission 84 operatively connected to at least one of said jaws 68', 68" suitable for causing the rotation of said jaw 68', 68" about the relative fixed pin or fulcrum 72 for locking/releasing the jaw.
According to an embodiment, transmission 84 comprises a connecting rod 88 hinged relative to a fixed support plate 14 of said device 4, visible in figures 1 and 2.
Preferably, connecting rod 88 is elastically influenced in rotation by elastic means 92.
The actuating means 64 comprise a bracket 96 suitable for influencing a free end of said connecting rod so as to cause the rotation thereof for moving jaws 68', 68".
Preferably, bracket 96 extends opposite the associable base 12 so as to end with an actuating button 86 on a front face 19 of circuit breaker 8, to be conveniently actuated from outside the associable circuit breaker 8.
Preferably, device 4 comprises insertion guides 98 in the associable base 12, suitable for ensuring the centring of circuit breaker 8 relative to the relative base 12 and correct coupling of jaws 68', 68" on the retaining means 40 of the associable base 12.
The guides comprise at least one pin suitable for inserting into relative seats 78 of the associable base. For example, such seats are made in the shape of sleeves 78 that extend from base 12 towards the associable circuit breaker.
The operation of a fixing device and of a circuit breaker according to the present invention shall now be described.
In a configuration of insertion of the circuit breaker into the relative base (figure 9), the circuit breaker is seated in the relative base 12 and is electrically connected to the electrical panel by the power connection terminals 27, 28. In figures 6, 7, 8, the power terminals 27 of circuit breaker 8 have been omitted only for the purpose of making the representation as clear as possible.
Pressing the actuating button 86, jaws 68, 68' open so as to allow the sliding of the hook portions on bars 44.
By further removing circuit breaker 8, bars 44 fit into seats 46, locking up. In such removed position, the power terminals 27, 28 of circuit breaker 8 are disconnected from the opposite terminals of base 12; therefore, in such removal configuration the circuit breaker is mechanically connected to the base, but comprises its electrical power terminals 27, 28 electrically disconnected from the base and therefore insulated from the electrical line circuit and from the electrical loading circuit.
In such removal configuration it is possible to run the test of the auxiliary functions of the circuit breaker with cut off circuit.
If one tries to insert circuit breaker 8 into the base, such insertion movement is prevented by the chamfers that stick against the bars 44.
Likewise, if one tries to remove the circuit breaker, such movement is prevented by the shape coupling between the hook portions and bars 44.
If there is the need of fully removing the circuit breaker, button 86 is pressed again so as to further spread the hook portions and disengage the hook portions from bars 44. In this way it is possible to fully remove the circuit breaker from the relative base.
As can be appreciated from the description, the fixing device, the base and the circuit breaker according to the invention allow overcoming the disadvantages of the prior art.
In particular, the circuit breaker of the present invention allows running tests of auxiliary functions of the circuit breaker with cut off system without the need of having to arrange the circuit breaker on makeshift surfaces in a precarious manner and without using extension cables of various types. The overall dimensions are thus reduced, the manual removal of heavy circuit breakers is prevented and the risks of accidental contact with electrical live parts are limited.
Thanks to the fixing device of the present invention, the circuit breaker is firmly constrained to the base, being arranged at a constant and guaranteed safety height. The tests can therefore be run in full safety.
Advantageously, the insertion of the circuit breaker into the relative base takes place with the aid of the insertion guides that ensure correct centring of the circuit breaker into the relative seat and safe coupling of the fixing device to the fixing means of the base.
Advantageously, the hooks of the fixing device always ensure the axial locking into position of the circuit breaker in removed position.
In fact, a possible attempt of insertion while the circuit breaker is in a removed configuration is prevented by the chamfers or inclined surfaces of the hooks; a possible attempt of removal on the other hand is prevented by the shape coupling of the hooks themselves with the base teeth.
The high safety of the coupling is due to the fact that the only way for releasing the circuit breaker from the removed position consists in an intentional pressure of the special release button.
Moreover it should be noted that the fixing device may be provided as an accessory capable of making a removable moulded case circuit breaker also provided with the additional removability feature.
A man skilled in the art may make several changes and adjustments to the fixing device and to the circuit breakers described above in order to meet specific and incidental needs, all falling within the scope of protection defined in the following claims.

Claims

Fixing device (4) for electrical circuit breaker (8), suitable for being arranged between an electrical circuit breaker (8) and a relative insertion base (12), the circuit breaker (8) comprising electrical connection terminals (27, 28) for being connected to a line circuit and a loading circuit, the base (12) comprising electrical terminals (37, 38) complementary to the electrical terminals (27, 28) of the circuit breaker and suitable for cooperating with the latter for electrically connecting the circuit breaker (8) to the electrical line and loading circuit breaker, the device (4) comprising:
- coupling means (48) to said base (12),

- actuating means (64) of said coupling means (48) suitable for locking and releasing the coupling means (48),
characterised in that
- the coupling means (48) are suitable for selectively constraining the circuit breaker (8) to the relative base (12) in an insertion position and in a removal position of the circuit breaker (8), in said removal position the circuit breaker (8) being mechanically constrained to the base (12) and said electrical terminals of the circuit breaker (27, 28) being electrically disconnected from said complementary connection terminals (37, 38) of the base (12).
Fixing device (4) according to claim 1, wherein the coupling means (48) comprise at least one jaw (68', 68") suitable for making a shape coupling with retaining means (40, 44) of the associable insertion base (12).
Fixing device (4) according to claim 2, wherein said at least one jaw (68', 68") is hinged about at least one fixed pin (72), arranged at a back face (18) of the associable circuit breaker, so as to directly face the retaining means (40) of the base (12).
Fixing device (4) according to claim 2 or 3, wherein said coupling means (48) comprise a pair of jaws (68', 68") suitable for making a shape coupling with retaining means (40) of the associable insertion base (12).
Fixing device (4) according to any one of claims 2 to 4, wherein said jaws (68', 68") are mechanically hinged to each other so that the relative opening/closing movement of the two jaws (68', 68") is synchronised.
Fixing device (4) according to claim 5, wherein one of said jaws (68', 68") comprises a pin (74) and the other one of said jaws (68", 68') comprises a fork portion (76) suitable for fitting on said pin (74), so as to obtain a hinge moving relative to a direction parallel to an axial insertion direction of the circuit breaker into the relative base (12).
Fixing device (4) for a circuit breaker according to any one of claims 2 to 6, wherein said at least one jaw (68', 68") comprises a hook end (80) suitable for locking to the retaining means (40) of an associable insertion base (12) according to a shape coupling.
Fixing device (4) for a circuit breaker according to claim 7, wherein said hook end (80) comprises a chamfer (82) directly facing the associable base (12) and suitable for opposing the insertion of the circuit breaker into the relative base (12).
Fixing device (4) for a circuit breaker according to any one of the previous claims, wherein said actuating means (64) comprise at least one transmission (84) operatively connected to at least one of said jaws (68', 68") suitable for causing the rotation of said jaw (68', 68") about the relative fulcrum locking/releasing the jaw (68', 68").
Device (4) according to claim 9, wherein said transmission (84) comprises a connecting rod (88) hinged relative to a fixed support plate (90) of said device.
Device (4) according to claim 10, wherein said connecting rod (88) is elastically influenced in rotation by elastic means (92).
Device (4) according to claim 9, 10 or 11, wherein said actuating means (64) comprise a bracket (96) suitable for influencing a free end of said connecting rod (88) so as to cause the rotation thereof for moving the jaws (68', 68").
Device (4) according to claim 12, wherein said bracket (96) extends opposite the associable base (12) so as to end on a front face (19) of the circuit breaker (8), to be actuated from outside the associable circuit breaker.
Fixing device (4) for circuit breaker according to any one of the previous claims, wherein said device comprises insertion guides (98) in an associable base (12), suitable for ensuring the centring of the circuit breaker (8) relative to the relative base (12) and correct coupling of the jaws (68', 68") on the retaining means (40) of the associable base (12).
Device (4) according to claim 14, wherein said guides (98) comprise at least one pin (74) suitable for inserting into relative seats of the associable base (12).
Support and electrical connection base (12) suitable for receiving an electrical circuit breaker (8) provided with a fixing device (4) according to any one of claims 1 to 15,
the base (12) comprising an insertion seat (42) for the electrical circuit breaker (8), and retaining means (40) suitable for obtaining a shape coupling with coupling means (48) of the circuit breaker (8),
the retaining means (40) being suitable for selectively constraining the circuit breaker (8) to the base (12) in an insertion position and in a removal position of the circuit breaker (8), in said removal position the circuit breaker (8) being mechanically constrained to the base (12) and electrically disconnected from the base (12).
Base (12) according to claim 16, wherein the retaining means (40) comprise at least one pair of bars (44) that form a meatus (46) suitable for seating the coupling means (48) of the coupling device of the associable circuit breaker (8).
Base (12) according to claim 17, wherein said bars (44) are offset relative to an axial direction, so as to determine a meatus (46) having such axial extension as to seat the coupling portions of the jaws (68', 68").
Base according to claim 17 or 18, wherein said bars (44) are offset relative to a vertical direction, perpendicular to said axial direction, so as to determine a meatus (46) having such vertical extension as to seat the coupling portions of the jaws (68', 68").
Base according to any one of claims 17 to 19, wherein the retaining means (40) comprise two pairs of bars (44) each forming a meatus (46) suitable for seating a hook of the fixing device.
Base according to any one of claims 16 to 20, wherein said base (12) comprises at least one centring element (78) suitable for receiving insertion guides (98) of the fixing device (4) so as to ensure the centring of circuit breaker relative to the base (12).
Circuit breaker (8) comprising a fixing device (4) according to any one of claims 1 to 15, said device being arranged at a back face (18) of the circuit breaker (8) directly facing an insertion seat (42) of the circuit breaker into the relative base (12).
Circuit breaker (8) according to claim 22, wherein said circuit breaker is a moulded case circuit breaker.
Circuit breaker group comprising a circuit breaker (8) according to any one of claims 22 to 23 and a base (12) according to any one of claims 16 to 21.