"Modular circuit breaker with a coupling system of the supporting fulcrum"

FIELD OF THE INVENTION

[0001] The present description refers to the technical field of electrical installations and, more particularly, it concerns a circuit breaker with coupling system of the supporting fulcrum.

STATE OF THE ART

[0002] As known, in modern electrical systems such as for example residential electrical installations, the use of modular electrical devices is widespread, such as modular circuit breakers or modular sockets, each one of them designed to serve a predetermined function. By conveniently combining such modular devices among them, it is possible to obtain relatively more complex units that make available the whole of the different functions.

[0003] A modular circuit breaker basically includes a supporting structure made of insulating material, or case, having the shape of a box and having an inner compartment for housing and for supporting the circuit breaker electromechanical components. In general, a modular circuit breaker further includes an operating button, for example a sliding button or a tilt button, coupled to the case. The modular circuit breaker includes at least one fixed electrical contact element and at least one mobile electrical contact element. By means of the operating button, a user can operate the modular circuit breaker and determine a rotation of the mobile electrical contact element with respect to the fixed electrical contact element, in order to establish or break an electrical connection between the mobile electrical contact element and the fixed electrical contact element.

[0004] In order to allow the rotation of the mobile contact element, a circuit breaker generally includes an electrically conductive supporting fulcrum housed inside the case. An embodiment of a circuit breaker with an electrically conductive supporting fulcrum is disclosed in European patent EP2304749 Bl .

[0005] In order to prevent undesired bounces between the mobile contact element and the supporting fulcrum, the supporting fulcrum is generally blocked in a fixed position inside the case. Reversible or irreversible blocking elements may be provided for this purpose. For example, the supporting fulcrum, after being positioned inside the case, may be blocked by one or more screws or one or more rivets.

[0006] In the prior art modular circuit breakers, the positioning and blocking operations of the supporting fulcrum inside the case are relatively complex, because the space available inside the case is generally narrow and only accessible from the open side of the case.

[0007] It is thus felt the need for implementing a modular circuit breaker wherein the supporting fulcrum is efficiently blocked inside the case and requiring that the positioning and blocking operations, during the assembling phase, are simpler with respect to the prior art solutions.

[0008] The object of the present description is to make available a modular circuit breaker being such as to fulfil the above described need with reference to the prior art modular circuit breakers.

[0009] Such object is achieved through a modular circuit breaker as generally defined in claim 1. Preferred and advantageous embodiments of the aforesaid modular circuit breaker are defined in the enclosed dependent claims.

[0010] The invention shall be better understood from the hereinafter detailed description of particular embodiments merely given by way of example but not limited to, with reference to the enclosed drawings briefly described in the following paragraph.

BRIEF DESCRIPTON OF THE DRAWINGS.

[0011] Figure 1 shows a perspective view of an embodiment of one modular circuit breaker including a case, a button slidingly constrained to the case and a key coupled to the button.

[0012] Figure 2 shows a side view of the modular circuit breaker of figure 1. [0013] Figure 3 shows a further perspective view of the modular circuit breaker of Figure 1 from which the key has been removed.

[0014] Figure 4 shows a top view of the circuit breaker case of Figure 1 from which all the components contained within the case have been removed.

[0015] Figure 5 shows a top view of the button of the modular circuit breaker of Figure 1.

[0016] Figure 6 shows a perspective view from below of the button of the modular circuit breaker of Figure 1. [0017] Figure 7 shows a partial cross-section perspective view of the modular circuit breaker of Figure 1, from which the key and some of the components contained inside the case have been removed.

[0018] Figure 8 shows a perspective view of the case of the modular circuit breaker of Figure 1, wherein some of the components contained inside the case are visible.

[0019] Figure 9 shows a partial cross-section perspective view of an enlarged part of the modular circuit breaker of Figure 1. [0020] Figure 10 shows a further partial cross-section perspective view of an enlarged part of the modular circuit breaker of Figure 1.

[0021] Figure 11 shows a side view of the modular circuit breaker of Figure 1 from which the key has been removed.

[0022] Figure 12 shows a partial cross-section perspective view of the case of the modular circuit breaker of Figure 1, wherein a supporting fulcrum inserted in the case is visible. [0023] Figure 13 shows a partial cross-section side view of the case and of the supporting fulcrum of Figure 12.

[0024] Figure 14 shows a perspective view of the supporting fulcrum of Figures 12 and 13.

[0025] Figure 15 shows a pressure transmitting member of the button of the modular circuit breaker of Figure 1.

[0026] Figure 16 shows a further perspective top view of the modular circuit breaker of Figure 1.

[0027] Figure 17 shows a perspective view of the supporting fulcrum, of the mobile contact holder support and of the fixed contact holder support.

[0028] Figure 18 shows a perspective view of the assembly of Figure 17 wherein it is also shown an elastic element, operatively coupled to the movable contact holder support . [0029] Figure 19 shows a perspective view of the assembly of Figure 17 wherein a rocking control member is also shown .

[0030] Figure 20 shows a further perspective view of the assembly of Figure 19.

[0031] Figure 21 shows a perspective view or the rocking control member of Figure 19

DE TAILED DESCRIPTION

[0032] With reference to the enclosed figures, it will now be described a particular non limiting embodiment of a modular circuit breaker 10. For the purposes of the present description, by modular circuit breaker 10 it is meant a circuit breaker intended to be installed on a supporting frame for wall installation placed beside other modular circuit breakers of the same type or in general beside other modular electrical devices, as for example, sockets. The circuit breaker 10 can be operated manually and can be used for example for controlling the electric power and/or the lighting in a residential or commercial building.

[0033] In the present description, by the term circuit breaker it is meant both a device for opening and closing a single electrical contact and a device for opening an electrical contact with the contemporary closing of another electrical contact and vice versa (diverter) .

[ 0034 ] For ease of explanation, hereinafter reference will be made to the case wherein the modular circuit breaker 10 is a push button breaker. For this reason in the present description reference will be made to the modular circuit breaker 10 also using the terms: push button circuit breaker, push button operated circuit breaker or modular push button operated circuit breaker. By push button operated circuit breaker it is meant a circuit breaker operated manually through a push button in order to determine one, or at least one, electrical switching. However, it is to be noted that the teachings of the present description can also be applied to modular circuit breakers with rocking control member of different types, including for example a tilt button or not including any operating button, not being for example operated by applying a manual pressure strength but by applying a traction strength, for example by means of a draw member. [ 0035 ] The modular circuit breaker 10 includes a supporting structure 20 made of electrically insulating material, e.g. plastic, preferably having, but not restrictively, approximatively a parallelepiped shape. The supporting structure 20, hereinafter called case, includes a bottom wall 21 and four lateral walls 20a, 20b, 20c, 20d joined to the bottom wall 21. The case 20 includes an open side 21' opposite to the bottom wall 21. The lateral walls 20a, 20b, 20c, 20d and the bottom wall 21 define an inner compartment adapted for housing the electromechanical components of the circuit breaker 10 and at least two electrical connection terminals CI, C2, C3. In the example shown in the Figures the inner compartment of the case 20 houses, without any limitation, three electrical connection terminals CI, C2, C3.

[0036] Preferably, the bottom wall 21 is integrated in the case 20, however in one alternative embodiment the bottom wall 21 might be a piece separated from the lateral walls 20a, 20b, 20c, 20d of the case 20 and coupled to them.

[0037 ] Preferably, the modular circuit breaker 10 includes a push button 30, that can be operated manually to command an electrical switching of the circuit breaker 10, having a body provided with lateral walls 30a, 30b, 30c, 30d crossing the open side 21' of the case 20. The push button 10 is adapted to slide with respect to the case 20 along a sliding axis Z-Z and along a stroke limited between a forward position and a backward position. For the purposes of the present description, by "forward position" it is intended a stopping position in the approaching movement of the push button 30 to the case 20, while by "backward position" it is intended a stopping position in the distancing movement of the push button 30 from the case 20. It is therefore clear that the terms "forward" and "backward" refer to the position of the push button 30 with respect to the case 20.

[0038] Preferably, the modular circuit breaker 10 includes a guide system adapted to guide the sliding of the push button 30 with respect to the case 20 along the sliding axis Z-Z.

[0039] Preferably, the guide system is a system of spatially distributed guides including first guide elements 22, 32 operatively interposed between the lateral walls 20a, 20b, 20c, 20d of the case 20 and the lateral walls 30a, 30b, 30c, 30d of the body of the push button 30.

[0040] Preferably, the system of spatially distributed guides also includes second guide elements 23, 24, 33, 34 spaced apart with respect to the first guide elements 22, 32 and placed with respect to the first guide elements 22, 32 at a lower distance from the bottom wall 21 of the case 20. Most precisely, friction surfaces cooperating between them of the first guide elements 22, 32, have a distance from the bottom wall 21 of the case 20 that is higher than the distance, with respect to the bottom wall 21 of the case 20, of friction surfaces cooperating between them of the second guide elements 23,24,33,34.

[0041 ] According to one advantageous embodiment the first guide elements 22, 32 include a first plurality of appendices 22 protruding from the lateral walls 20a, 20b, 20c, 20d of the case 20 towards the lateral walls 30a, 30b, 30c, 30d of the push button 30 and a second plurality of appendices 32 protruding from the lateral walls of the push button 30 towards the lateral walls 20a, 20b, 20c, 20d of the case 20 and each being adapted to contact a respective appendix 22 of the first plurality of appendix 22 in order to slide thereon when the push button 30 slides with respect to the case 20.

[0042] In the non-limiting exemplary embodiment shown in the Figures four appendices 22 protruding from the lateral walls 20a, 20b, 20c, 20d of the case 20 as well as four corresponding appendices 32 protruding from the lateral walls 30a, 30b, 30c, 30d of the push button 30 are provided. [0043] According to one advantageous embodiment, the first plurality of appendices 22 and the second plurality of appendices 32 allow the lateral walls 30a, 30b, 30c, 30d of the push button 30 to be spaced from the lateral walls 20a, 20b, 20c, 20d of the case 20 when the push button 30 slides with respect to the case 20. Thereby, in fact, the push button operated switch 10 is less vulnerable to an undesired dust or sand intrusion within the lateral walls 20a, 20b, 20c, 20d of the case 20 and lateral walls 30a, 30b, 30c, 30d of the push button 30 that would otherwise cause a jamming inside a circuit breaker wherein, due to a wide overlapping between the lateral walls of the push button 30 and those of the case 20, there are wider friction surfaces.

[0044] According to one preferred embodiment, the aforesaid protruding appendices 22, 32 are linear appendices, which in the shown example extend linearly along axes that are parallel between them and parallel to the sliding axis Z-Z.

[0045] According to one preferred embodiment, the lateral walls of push button 30 are parallel in twos and define edges 32', each of them being defined by a pair of adjacent lateral walls 30a, 30b, 30c, 30d of push button 30. Each appendix 32 of the second plurality of appendices is arranged on a corresponding edge 32'. Preferably, the edges 32' are bevelled.

[0046] According to one advantageous embodiment, the second guide elements 23, 24, 33, 34 are staggered with respect to the first guide elements 22, 32. In other words, the second guide elements 23, 24, 33, 34 are closer to some of the first guide elements 22, 32 and further from other first guide elements 22, 32.

[0047 ] Preferably, with reference to Figures 4, 6 and 7 the second guide elements 23, 24, 33, 34 include a guide seat 23 and a guide pin 33 having an end portion 34 slidable in the guide seat 23. In the non-limiting exemplary embodiment shown in the Figures, the guide pin 33 extends from the body of the push button 30 towards the bottom wall 21 of the case 20 while the guide seat 23 is fixed to the bottom wall 21 of the case 20. Preferably, the guide pin 33 is integrated in the push button 30 and protrudes from the body of the push button 30 towards the bottom wall 21 of the case 20. Preferably, the body of the push button 30 and the guide pin 33 form a single piece. [0048] According to one advantageous embodiment, the aforesaid end portion 34 of the guide pin 33 has a cross- shaped cross-section. By cross-shaped cross-section, it is intended a section on a plane that is perpendicular to the sliding axis Z-Z. In the particular embodiment shown in the Figures, the aforesaid cross-shaped cross-section includes a circular central part from which four arms originate forming a Greek cross.

[0049] According to one advantageous embodiment, the guide pin 33 does not interfere with the lateral walls 20a, 20b, 20c, 20d of the case 20 during the sliding movements of the push button 30 with respect to the case 20. In other words, the guide pin 33 is spaced apart from the lateral walls 20a, 20b, 20c, 20d of the case 20 so as to avoid having friction surfaces among the lateral walls of the case 20 and the guide pin 33 itself.

[0050] With reference to Figures 4 and 7, according to one embodiment the guide seat 23 includes four lateral walls 24 parallel in twos. Preferably, the lateral walls 24 of the guide seat 23 are separated from one another and joined to the bottom wall 21 of the case 20. In one alternative embodiment the guide seat 33 may be a continuous collar, having a quadrangular or circular section. In the particular example shown, the lateral walls 24 are integrated in the bottom walls 21 of the case 20, protruding from it towards the push button 30.

[0051] With reference to Figure 8 the push button operated circuit breaker 10 includes at least one elastic element 40 adapted to exert a pushing force on the push button 30 in order to bring back or keep the push button 30 in the backward position in absence of external forces. In the particular embodiment shown in Figure 8 the modular circuit breaker 10 comprises two elastic elements 40 having the form of two helicoidal springs 40. In particular, in the shown example, the circuit breaker 10 also includes a diaphragm 41 housed inside the case 20 and the elastic elements 40 are operatively inserted between the diaphragm 41 and the body of the push button 30, each having for example an end portion inserted in a correspondent recessed seat 39 provided in the body of the push button 30 (Figure 6) . Also in the diaphragm 41 recessed seats having the same function may be provided.

[0052] With reference to Figures 8-10, in order to stop the push button 30 in the backward position, the push button operated switch 10 preferably includes a first stopping system including contact surfaces 251, 351 of the lateral walls of the case 20 and of the lateral walls of the push button 30 respectively, which are abutting to each other when the push button 30 is in the backward position. In one particularly advantageous embodiment, the first stopping system includes a button alignment system of the push button 30 including alignment elements 250, 350 engaging with each other starting from a given point on during the sliding movement of the push button 30 from the forward position towards the backward position. Such alignment elements 250, 350 allow to progressively align the push button 30 with respect to a reference plane R_P (Figure 11) that is perpendicular to the sliding axis Z-Z.

[0053] According to one advantageous embodiment, the aforesaid alignment elements 250, 350 include at least a variable cross-section guide 250, and a corresponding variable cross-section slider 350 adapted to be inserted inside the variable cross-section guide 250, starting from a given point on during the course of the push button 30 before reaching the backward position and up until reaching it. Preferably the variable cross-section guide 250 is a tapered guide, having a decreasing cross- section in the direction towards the reference plane R_P . In this case, for example, the variable cross-section slider 350 is wedge-shaped.

[005 ] According to one advantageous embodiment, in order to further increase the precision of the alignment of the push button 30 with respect to the reference plane R_P and to guarantee a better coupling between the push button 30 and the case 20, the contact surfaces 251, 351 are surfaces that, in the backward position of the push button 30, lie on a plane I_P inclined with respect to the reference plane R_P .

[0055] According to one particularly advantageous embodiment, the modular circuit breaker 10 includes complementary snap-fit elements 25, 35 provided on the lateral walls of the case 20 and on the lateral walls of the body of the push button 30. The aforesaid snap-fit elements 25 are shaped in order to facilitate a forced insertion of the body of the push button 30 through the open side 21' of the case 20 in the assembling phase of the push button-case assembly and, once they pass a snapping position, to make an interlocking coupling between the push button 30 and the case 20, based on which the push button 30 is slidingly constrained to the case 20.

[0056] In the particular example represented in the Figures, without limitation, the said snap-fit elements 25, 35 include four snap-fit teeth 25 on the lateral walls of the case 20 and four complementary snap-fit teeth 35 arranged on the lateral walls of the body of the push button 30. Preferably, the snap-fit teeth 25, 35 are arranged at the corners of a rectangle or square lying on a plane that is perpendicular to the sliding axis Z-Z. [0057 ] According to one particularly advantageous embodiment, the above described interlocking snap-fit elements 25, 35 carry the above described alignment elements 250, 350 and preferably the above described contact surfaces 251, 351 too. [0058] According to one preferred embodiment, in order to stop the push button 30 in the forward position, the modular circuit breaker 10 includes a second stopping system including contact elements 26, 36 respectively provided on the lateral walls of the case 20 and on the lateral walls of the body of the push button 30. In the particular example shown, the aforesaid contact elements 26, 36 include two small blocks 36 protruding from opposite walls 30b, 30d of the push button body 30 and stopping seats 26 provided on two opposite lateral walls 20b, 20d of the case 20.

[0059] The modular circuit breaker 10 includes an electrically conductive supporting fulcrum 50 housed inside the case 20. As known, in a circuit breaker a supporting fulcrum 50 serves as a supporting means for a mobile electrically conductive switching member, being in particular rotatable, carrying at least a mobile electrical contact element. The aforesaid mobile electrically conductive switching member will be called in the present description rotatable contact holder support. The supporting fulcrum 50 is for example made of folded and punched metal foil.

[0060] In order to guarantee a stable fixing of the supporting fulcrum 50 to the case 20, the case 20 includes a housing seat 27 of the supporting fulcrum 50 and the modular circuit breaker 10 includes a snap-fit coupling system adapted to fix the supporting fulcrum 50 to the case 20 in the housing seat 27. Preferably, the housing seat 27 is arranged inside the case 20 on the bottom wall 21 and the snap-fit coupling system includes at least a coupling elastic tooth 28 adapted to hook the supporting fulcrum 50 to the bottom wall 21 of the case 20. Preferably, the aforesaid coupling elastic tooth is integrated in the bottom wall 21 of the case 20 and forms a single piece with the latter. In the example shown in the Figures, the snap-fit coupling system includes a plurality of coupling elastic teeth 28, in particular three coupling elastic teeth 28.

[ 0061 ] According to one advantageous embodiment that allows to simplify the manufacturing of the case 20, beneath the coupling elastic tooth 28, the bottom wall 21 of the case 20 has a pass-through hole 28'. Thereby, it is usefully avoided having to mould in the bottom wall 21 of the case 20 undercut opposite surfaces.

[ 0062 ] According to one preferred embodiment, the coupling elastic tooth 28 has a free end portion and an opposite end portion constrained to the bottom wall 21 of the case 20 and the free end portion is such that it engages with a peripheral portion of the supporting fulcrum 50. [ 0063 ] According to one advantageous embodiment, the snap-fit coupling system includes at least two snap-fit coupling teeth 28 arranged at opposite sides with respect to the supporting fulcrum 50.

[ 006 ] According to one embodiment, the housing seat 27 of the supporting fulcrum 50 is a recessed seat defined in the bottom wall 21 of the case 20. Preferably, the fulcrum 50 includes a support and contact portion 51 that is shaped so as to form a groove, for example having a V- shaped cross section, housed inside the recessed housing seat 27. Preferably, the supporting fulcrum 50 also includes a connecting portion 53, being part of a connecting terminal CI of the modular circuit breaker 10. The connecting terminal CI includes a screw 54 and a clamping plate 55, and the screw 54 crosses the connecting portion 53 of the supporting fulcrum 50 to engage with the clamping plate 55. According to one advantageous embodiment, between the support and contact portion 51 and the connecting portion 53 the supporting fulcrum 50 includes an intermediate portion 52 forming a connecting inclined plane between the support and contact portion 51 and the connecting portion 53.

[0065] According to one particularly advantageous embodiment, the modular circuit breaker 10 also includes an anchoring system 59, 29 of the supporting fulcrum 50 to the case 20, in particular to the bottom wall 21 of the case 20. For example the anchoring system 59, 29 includes a folded little wing 59 integrated in the supporting fulcrum 50 and an anchoring seat 29 (visible in Figure 4) arranged inside the bottom wall 21 of the case 20 housing the folded little wing 59. This allows to stabilise the supporting fulcrum 50 position also with respect to the external stresses that affect for example the supporting fulcrum 50 during the wiring operations of the circuit breaker 10, for example caused by the clamping of the connecting terminal CI.

[0066] Apart from the specific example shown in the drawings, more general or more specific embodiments have been basically described so far, wherein the circuit breaker 10 is a generic push button operated circuit breaker.

[0067 ] Hereinafter some embodiments will be described wherein the circuit breaker 10 is a push button operated circuit breaker with a rocking control member. An example of a push button operated circuit breaker with rocking control member is, for example, disclosed in European patent EP1866944. Apart from the particular embodiment described in such patent, it is to be noted that by push button operated circuit breaker with rocking control member it is meant in general a circuit breaker operated by a sliding push button including a rotatable switching control member.

[0068] With reference to Figures 3, 5, 6, according to one advantageous embodiment the push button 30 includes a pressure transmitting member 60 rotatably constrained to the body of the push button 30. The pressure transmitting member 60 is adapted to rotate into two opposed directions starting from a rest position (or central position) and the push button 30 includes at least an elastic element 61 adapted to bring the pressure transmitting member 60 back to the angular rest position after a rotation of the same. With reference to Figures 6 and 15, it is to be noted that the pressure transmitting member is adapted to rotate around the rotation axis Al- Al (that will be called third rotation axis) . [0069] According to one advantageous embodiment, that allows a user to manually operate the push button 10 perceiving a very limited resistance, the above said elastic element is, or includes, a wire spring 61 and preferably a rectilinear wire spring. The aforesaid spring 61 is, for example, a wire spring made of spring steel. It has been observed that a wire spring 61 with reduced section, for example with a diameter included between 0,25 mm and 0,75 mm and for example equal to 0,5 mm, is able to bring the pressure transmitting member 60 back to the angular rest position and is able to resist to the stresses generated when the push button 30 is manually operated.

[0070] Preferably, the aforesaid wire spring 61 has two opposite end portions 62 constrained to the push button 30 and a central portion 63 adapted to exert an elastic strength on the pressure transmitting member 60. Preferably, referring to Figure 15, the pressure transmitting member 60 includes a central portion 600 and two appendices 601 and 602 originating from the central portion 600. Preferably, the central portion 600 includes a channel 630, as for example a recess or hole, crossed by the central portion 63 of the wire spring 61.

[0071 ] Referring to Figure 16, according to one advantageous embodiment, the body of the push button 30 includes a pass-through opening 360, crossed by the pressure transmitting member 60, thereby the wire spring 61 is arranged on one side of the pass-through opening 360 together with at least one part of the central portion 600 of the pressure transmitting member 60, while the remaining part of the pressure transmitting member 60 is arranged on the other side of said pass-through opening 360.

[0072] With reference to Figure 15, according to one further advantageous embodiment, the pressure transmitting member 60 includes two opposite hinge pins 610 that originate from the central portion 600 of the aforesaid member. For example, the two hinge pins 610 are cylindrical pins. Such hinge pins 610 are oriented along the rotation axis Al-Al of the pressure transmitting member 60. According to one advantageous embodiment, in order to simplify the assembly of the push button 30, the latter includes two semicircular recesses 310 (visible in Figure 6) , or generally having the shape of an arc of the circle, aligned along the rotation axis Al-Al of the pressure transmitting member 60, each of which is adapted to partially receive a respective hinge pin 610. In this case, the wire spring 61, apart from serving as elastic means to restore the pressure transmitting member 60 into its rest position, also serves advantageously as fixing element of the member 60 to the push button 30.

[0073] According to one advantageous embodiment, referring to Figure 16, the push button 30 includes a fixing seat 361 of the wire spring 61 made in the thickness of the bottom wall 31 of the push button 30 and that in the embodiment is placed on top of the pass- through opening 360 of the push button 30. Preferably, such fixing seat 361 includes two grooves 362 aligned to each other along the direction of prevalent longitudinal extension of the wire spring 61 and are crossed by the end portions 62 of the wire spring 61. Preferably, the end portions 62 of the wire spring 61 protrude beyond such grooves 362 from opposite sides with respect to the central portion 63 of the wire spring 61. Conveniently, the fixing seat 361 of the wire spring 61 includes stopping elements 365 adapted to limit or prevent an undesired translation of the wire spring 31 with respect to the push button 30. Such translation might in fact determine and undesired detachment of the wire spring 61 from the push button 30 and, thus, in the embodiment too of the pressure transmitting member 60.

[0074] With reference to Figure 7, the aforesaid pressure transmitting member 60 is such that it contacts, from a certain point on during the sliding of the push button 30 from the backward position to the forward position, a switching rocking control member 70, e.g. a bistable member, included in the push button operated circuit breaker 10 in case said circuit breaker 10 is a push button circuit breaker with rocking operating mechanism. After such contact, the pressure transmitting member 60 starts rotating with respect to the rest position, and during a further advancement of the push button 30, it determines a rotation of the rocking control member 70 starting from a first operative position until it reaches a second operative position. At this point, if the pressure of the push button 30 is released, it will be able to return back to the backward position and the pressure transmitting member 60 can return back to the rest position whilst the control rocking member 70 will be able to remain in the second operative position, if it is a stable position, or, in the opposite case, return back to the first operative position (e.g. as a result of a call-back strength performed by an elastic element) . In case the control rocking member 70 returns in the first operative position, a further pressure of the push button 30 will determine a sequence of movements as the above described one. On the contrary, in case the control rocking member 70 remains in the second operative position, at the moment of a further pressure of the push button 30 through a sequence of movements similar to the above described one, it will be able to return in the first operative position and remain there when the push button is released and until a subsequent pressure of the push button.

[ 0075 ] With reference to Figures 17-21, the modular circuit breaker 1 includes at least a fixed electrical contact element 92,92' (hereinafter also called fixed contact element) and at least a mobile element of electrical contact 82,82' (hereinafter also called mobile contact element) and the rocking control member 70, by moving as a result of the pressure transmitted by the pressure transmitting member 60, determines a rotation of the rotatable contact holder support 81 around a rotation axis A3-A3 (hereinafter also called first rotation axis) that in its turn, rotates the mobile electrical contact element 82 between a first and a second operative position, being angularly spaced from one another. In the non-limiting embodiment shown in Figures 17-21, the circuit breaker 10 includes two opposite mobile electrical contact elements 82,82' and two fixed electrical contact elements 92,92', being spaced apart and each other fronted. In this case the modular circuit breaker 10 is thus a two-way diverter, whereby in one of the aforesaid operative positions the mobile contact element 82 is in contact with a fixed contact element 92 and the mobile contact element 82' is spaced apart from the other fixed contact element 92' while in the other operative position the mobile contact element 82 is spaced apart from the fixed contact element 92 and the mobile contact element 82' is in contact with the other fixed contact element 92'. However, it is to be noted that the teachings of the present description can be easily applied from an expert in the field even to a modular circuit breaker 10 having a single fixed electrical contact element and a single mobile electrical contact element. Thus, it is possible to generalise by stating that the mobile electrical contact element 82,82' rotates around a rotation axis A3-A3 between two operative positions angularly spaced between them in order to break or deviate an electrical circuit. From now on, reference will be made however, without limitation, to the case wherein the modular circuit breaker 10 includes two mobile electrical contact elements 82,82' and two fixed contact elements 92,92'. In such a case the modular circuit breaker 10 includes two fixed contact holder supports 91,91' to which the fixed contact elements 92,92' are respectively fixed, e.g. welded. The fixed contact holder supports 91,91' are made of electrically conductive material, e.g. copper, and each one includes a connecting portion 93,93'. Preferably, each connecting portion 93,93' is for example part of a corresponding electrical connecting terminal C2, C3 of the modular circuit breaker 10. Each connecting terminal C2, C3 includes a screw 94, 94' and a clamping plate 95, 95' and each screw 94, 94' is such that crosses the respective connecting portion 93,93' for engaging with an associated clamping plate 95,95'.

[0076] The mobile electric contact elements 82, 82' are for example two opposite electrically conductive pads, e.g. made of sintered silver, fixed, e.g. welded, at the opposite sides of an end portion of a mobile contact holder support 81, also made of electrically conductive material, e.g. copper. It is thus clear that in this embodiment the mobile electrical contact elements 82,82' are electrically connected between them. The opposite end portion of the mobile contact support 81 lies on the supporting fulcrum 50 and in particular on the support and contact portion 51 of the supporting fulcrum 50. The mobile contact holder support 81 rotates around a first rotation axis A3-A3, in the example defined by the supporting fulcrum 50, to rotate the mobile electrical contact element 82,82' between the first and the second operative portion and vice versa. For example, the mobile contact holder support 81 is an L-shaped plate having a larger base 810 lying on the supporting fulcrum 50 and a more narrow arm 811 of the base 810 that protrudes from the base 810 and on whose end portion opposite to the base 810 the mobile electrical contact elements 82,82' are fixed.

[0077 ] According to one embodiment, the rocking control member 70 includes a body 75, preferably made of electrically insulating material, e.g. plastic, rotatably hinged to the case 20 in order to rotate around a rotation axis A2-A2 (herein called second rotation axis too) , parallel to a first rotation axis A3-A3, so as to rotate the rotatable contact holder support 81. Preferably, the second rotation axis A2-A2 is parallel both to the third rotation axis Al-Al and to the first rotation axis A3-A3. Preferably, the body 75 of the rocking control member 70 is rotatably hinged to the case 20. [0078] According to one advantageous embodiment, in order to reduce the axial encumbrance of the modular circuit breaker 10, the body 75 of the rocking control member 70 is shaped in such a way that the rotatable contact holder support 81 in the rotation around the first rotation axis A3-A3 can cross the second rotation axis A2-A, that is the rotation axis of the body 75 of the rocking control member 70.

[0079] Preferably, the body 75 of the rocking control member 70 includes a contact portion 72 having two shaped surfaces 701, 702 intended to be alternatively contacted and pushed by the pressure transmitting member 60, and in particular by the two appendices 601,602. Preferably the two shaped surfaces 701, 702 are two stepped surfaces.

[0080] According to one embodiment, the body 75 of the rocking control member 70 includes a bridge portion 71 bypassing an operative space 710 in which the rotatable contact holder support 81, or an end portion thereof, as for example an end portion of the arm 811, is free to rotate. For example, the bridge portion 71 includes at least a bended bridge arm 711, 712, 713, preferably two coplanar bended bridge arms 711, 713 originating from two different points of the body 75 and joining in the same point. In the particular embodiment shown, the bridge portion 71 includes three bended bridge arms 711, 712, 713 originating from three different points of the body 75 and joining in the same point to form a cage structure that defines the operative area 710 within which the rotatable contact holder support 81, or an end portion thereof, as for example an end portion of the arm 811, is free to rotate. According to one possible embodiment, the bridge portion 71 may include a continuous bridge wall provided with a recess or a pocket within which the rotatable contact holder support 81, or an end portion thereof, is free to rotate. [0081 ] According to one advantageous embodiment, as in the example shown in the Figures, the bridge portion 71 bypasses also a space occupied by the fixed contact holder support 91,91', by the fixed electrical contact element 92,92' and by the mobile electrical contact element 82,82'. Thereby, the bridge portion 71 bypasses a space region of the modular circuit breaker 10 in which the joining and separation between the mobile electrical contact element 82,82' and the fixed electrical contact element 92,92' occurs. [0082 ] According to one embodiment, the rocking switching control member 70 includes two opposite coupling elements that allow the rotatably coupling of the control member 70 to two opposite lateral walls of the case 20. In the particular example shown in the figures, the aforesaid coupling elements include two opposite cylindrical shaped pins 76 protruding from the body 75 along the rotation axis A2-A2 in opposite directions. According to one advantageous embodiment, one of the aforesaid pins 76 protrudes from the contact portion 72 and the other one of said pins protrudes from the bridge portion 71. For example, such pins 76 are inserted in corresponding pass- through holes or recesses 276 arranged in two opposite lateral walls of the case 20.

[0083] According to one embodiment, the body 75 of the rocking control member 70 includes a portion 73 containing an internally hollow seat adapted to receive an elastic element, e.g. an helicoidal spring 77, operatively inserted between the rocking control member 70 and the mobile contact holder support 81. For example, the mobile contact holder support 81, and in particular its base 810, includes a protruding appendix 87 inserted inside the helicoidal spring 77.

[008 ] According to further embodiments, in the body of the rocking control member 70 further accessory elements can be provided, such as a ring 78 to which a draw wire can be tied and/or fixed allowing to operate the rocking control member by means of a draw member and/or a wall 79 with a recess (not visible in the drawings because it points to the bottom wall 21 of the case 20) adapted to receive an end of an elastic element (as for example an helicoidal spring) adapted to make the rocking control member 70 a monostable member.

[0085] Though it has been described a specific and detailed embodiment of modular circuit breaker 10, it must be observed that the teachings of the present description extends in general to a modular circuit breaker 10 including a case 20 made of electrically insulating material, at least a rotatable electrical contact element 82,82' and at least a fixed electrical contact element 92,92', a supporting fulcrum 50 of the rotatable electrical contact element 82,82', wherein the supporting fulcrum 50 is adapted and configured for supporting the rotatable electrical contact element 82,82' in the rotation of the latter around a rotation axis A3-A3 in order to establish or break an electrical contact between the rotatable electrical contact element 82,82' and the fixed electrical contact element 92,92', wherein the case 20 includes a housing seat 27 of the supporting fulcrum 50 and wherein the modular circuit breaker 10 includes a snap-fit coupling system adapted to block the supporting fulcrum 50 to the case 20 in the housing seat 27.

[0086] As clearly shown from the above description, the proposed modular circuit breaker 10 allows to fully achieve the planned scopes in terms of overcoming the drawbacks of the prior art circuit breakers. As a matter of fact, thanks to the provision of a snap-fit coupling system adapted to block the supporting fulcrum 50 to the case 20 in the housing seat 27, the positioning and blocking of the supporting fulcrum 50 inside the case 20 does not require complex operations and is at the same time quick and effective.

[0087 ] Sub ect to the principle of the invention, the embodiments and the implementation details shall be widely varied with respect to what has been said and shown for exemplary purposes but not limited to, without detaching from the field of the invention as defined in the enclosed claims.