EP4576152A1

EP4576152A1 - Circuit breaker and method of assembling an operating mechanism on a circuit breaker molded base

Info

Publication number: EP4576152A1
Application number: EP24222151.3A
Authority: EP
Inventors: Gabriel ARAÚJO FRIEDMANN; Fábio DECKER DE SOUZA
Original assignee: WEG Drives and Controls Automation Ltda
Current assignee: WEG Drives and Controls Automation Ltda
Priority date: 2023-12-22
Filing date: 2024-12-20
Publication date: 2025-06-25
Also published as: CN120261231A

Abstract

The present invention relates to a circuit breaker (100) comprising a molded base (200), an operating mechanism (300) together with a separable pair of contacts (630, 631) and a molded cover (400), wherein: the molded base (200) comprises a plurality of grooves (220), a plurality of shoulders (222), a plurality of through openings (224); and said operating mechanism (300) comprises a plurality of side plates (310), at least one perpendicular protrusion (320), and a plurality of legs (330); wherein each leg (330) comprises a tab (364) comprising folding lines (375), and wherein said tab (364) can be inserted into said through openings (224) of at least one pair of grooves (220) of said molded base (200) and be folded so as to position at least one pair of grooves (370) over shoulders (222) of said molded base (200) of said circuit breaker (100); and the present invention also relates to a method of assembling said operating mechanism (300) on said molded base (200).

Description

Technical Field

The present invention refers to the field of fixation of the operating mechanisms of electrical contacts. The present invention also belongs to the field of fixation of mechanisms for operating contacts to the base of a molded case circuit breaker.

Introduction

The present invention relates to a circuit breaker, more specifically to a system for fixation of the operating mechanism of a circuit breaker obtained through conformation.

Background of the Invention

As is common knowledge for a skilled person, molded case circuit breakers can have their functioning based on thermal, magnetic, thermomagnetic or even electronic principles, through the movement of electrical contacts, and can be used, above all, to protect electrical circuits exposed to short-circuits and/or electrical overloads generated by electrical current levels that exceed a nominal limit previously established by linking input and outlet terminals, connected to the electrical supply circuit to be protected.
Thus, it can be seen that circuit breakers work fundamentally in a similar way to electrical switches, i.e., work in such a way as to change the electrical conduction state of an electrical circuit between the "on" (ON) and "off" (OFF) states. In addition to operating automatically, conventional circuit breakers also comprise an operating handle that can be operated by a user. In this type of molded case construction, it is typical for the current carrying capacity to support relatively high values, reaching up to 1600A, or even more. In particular, it is common for circuit breaker handles to remain stationary in a trip position (TRIP) after a fault event, until a new trigger.
This type of electrical device requires the performance of several tests to ensure the safety and correct functioning of each circuit breaker manufactured. Therefore, a solution that can optimize the steps of assembling, testing, and replacing defective components would be able to optimize both the time and costs involved in manufacturing circuit breakers.

Prior art

Known prior art solutions for circuit breakers of the nature discussed here can be verified in prior art documents such as European document EP 1010187 , entitled "Power circuit breaker with an actuating shaft", which contemplate, e.g., a power circuit breaker comprising a contact arrangement, a drive arrangement for operating said contact arrangement and an actuating axis that transmits a driving force from the driving force arrangement to the contact arrangement to open or close the latter. A bearing arrangement for the drive bar has at least one bearing body which is joined to a pole assembly group, said assembly group containing said contact arrangement. According to this solution, a unit is configured that can be tested independently of the other circuit breaker assembly groups. In multipole circuit breakers, a common drive bar may be used for all contact arrangements or pole assembly groups. Said drive bar is mounted in an approximately central position within a main bearing body and its ends are mounted in auxiliary bearing bodies.
Despite showing a circuit breaker comprising groups of individual units of mechanisms at each pole, which can be tested independently of the other groups of interrupting assembly, EP 1010187 presents a circuit breaker device that uses screws to fix the internal mechanisms, and it is dependent of the assembly of the body/cover interface before its internal components can be tested.
Another patent document whose solution can be mentioned is document US 5023582 , entitled "Molded case circuit breaker compact latch asssembly", which refers, e.g., to a molded case circuit breaker that employs a multiple latch assembly to maintain the circuit breaker operating mechanism in a closed condition. The multiple latch assembly includes three separate latch levers mounted on a common latch support frame.
Similar to other known solutions, US 5023582 in particular, describes an arrangement that aims only to seal the internal mechanisms of circuit breakers and fix the internal components through pins, without worrying about providing a device that can be tested before its complete assembly.
It was observed in the prior art US 4894747 a circuit breaker mechanism that uses leg twisting as a form of fixation to the base of a circuit breaker.
Attempts have been made in the prior art US 4864263 , EP 0209054 , and US 4563557 of circuit breaker mechanisms that bend legs as a means of fixation to the base of a circuit breaker.
Finally, it is worth mentioning that several other prior art solutions can be verified in other patent documents such as JP 4126865 , EP 0395326 , US 4894632 , and EP 0188482 . These documents also identify circuit breakers that use pins, screws, and similar items to fix their internal components, in addition to not being subject to qualification tests before their complete assembly.
Therefore, the state of the art does not provide robust, simple, and low-cost solutions for a circuit breaker capable of being tested in advance, and which does not use pins, screws, and similar items to fix its internal components before its complete assembly.
Some of these solutions fail because torsional deformations represent internal stresses in the materials that can lead to the rupture of the fixation ends. Others fail because they do not completely lock the mechanism in the different degrees of freedom. Others still fail because they use additional components. They also fail because they allow deformations or risk of rupture of the molded base material, having to be supported by a protective washer, or because they are complex.
There is therefore space for a circuit breaker that:

a) allows for the performance of functioning and qualification tests and even critical tests of submission to driving forces with the product open, before its complete assembly or closing with a cover, without implying design changes or expenditure on auxiliary fixing devices or apparatus;
b) ensures a high-quality, low-cost product, with low raw material consumption and high robustness for the proposed application;
c) does not use screws, reinforcement washers, pins, and equivalent fixing elements dedicated or exclusive to fixing the operating mechanism inside the molded base;
d) allows the locking of the operating mechanism by controlled deformation of at least one pair of tabs of at least two legs of the mechanism, requiring a reduced conformation force and which does not deform the molded base; and
e) demands and allows the use of a simple conformation tool from this pair of tabs;
f) that the locking achieved by means of the deformation of tabs is given in two degrees of freedom.

Objectives of the invention

One of the objectives of the invention is to provide a circuit breaker, according to the characteristics of claim 1 of the attached set of claims.
Yet another object of the invention is to provide a method of assembling an operating mechanism on a circuit breaker molded case, according to the characteristics of claim 12 of the attached set of claims.
Another object of the invention is to impede any translation on the X and Y axes, so as to firmly fix the operating mechanism on the molded base and impede its translation and rotation.
Another objective of the invention is to allow for the performance of functioning and qualification tests in critical tests of submission to driving forces with the product open, before its complete assembly or closing with a cover, without implying changes to the design or expenditure on auxiliary fixing devices or apparatus.
Allow for a simple inspection of the functioning of moving parts, without destroying components of the casing or using transparent or special components for this purpose, or even difficult filling with resin and subsequent cutting of components to observe positions in functioning analysis.
Another objective of the invention is not to use screws, reinforcement washers, pins, and equivalent fixation elements dedicated to fixation the circuit breaker operating mechanism, and not to deform the molded base.
Another objective achieved by the present invention is to allow said operating mechanism of said circuit breaker can easily be replaced during maintenance.
Additional characteristics and details thereof are presented in the dependent claims.

Brief description of the drawings

For a better understanding and visualization of the object, the present invention will now be described with reference to the appended figures, representing the obtained technical effect through an exemplary embodiment without limiting the scope of the present invention, in which, diagrammatically:

Figure 1:: shows an upper perspective view of a circuit breaker comprising an operating mechanism, according to the present invention;
Figure 2:: shows a lower perspective view of said circuit breaker in Figure 1 and the indication of a detail "F";
Figure 3:: shows a view of the enlarged partial detail "F" of a region of lower grooves of said circuit breaker in Figure 1;
Figure 4:: shows an enlarged detail view of one of said grooves in the lower region seen in said Figure 3;
Figure 5:: shows a perspective view of said operating mechanism of a circuit breaker, according to the present invention;
Figure 6:: shows an enlarged partial view of a leg of said operating mechanism seen in said Figure 5;
Figure 7:: shows a cross-sectional side view of said circuit breaker seen in said Figure 1, comprising a plurality of tabs of a plurality of legs of said mechanism introduced into a molded base;
Figure 8:: shows a cross-sectional side view of said circuit breaker seen in said Figure 1, where said mechanism is seen in assembly, comprising a plurality of tabs of a plurality of legs of said mechanism inserted into a molded base, where said ends of said plurality of legs are seen conformed;
Figure 9:: shows a lower perspective view of a molded cover of said circuit breaker seen in said Figure 1;
Figure 10:: shows a longitudinal sectional view of said circuit breaker seen in said Figure 1; and
Figure 11:: shows an upper perspective view of said circuit breaker seen in said Figure 1 shown open and without its molded cover, according to the present invention.

Detailed description of the drawings

Figure 1 shows, in an upper perspective view, a circuit breaker (100), comprising a molded base (200), an operating mechanism (300), a molded cover (400), and a cover (500).
Figure 2 shows a bottom perspective view of said circuit breaker (100), comprising said molded base (200), molded cover (400), and cap (500) seen in said Figure 1, highlighting the lower fraction of said molded base (200) which comprises at least one lower region (210), which in turn comprises at least two grooves (220), in addition to an indication of a Detail "F" to be seen in Figure 3, a transverse axis "X", a longitudinal axis "Y", and a lifting axis "Z".
Figure 3 presents an enlarged Detail "F" view of said lower region (210) of said molded base (200) of said circuit breaker (100), wherein said molded base (200) (best seen in Figure 2) further comprises said plurality of perpendicular walls (221), at least two said shoulders (222) and at least two said inclined surfaces (223). Furthermore, at least one pair of lower ends (361) of said operating mechanism (300) are visible from the grooves (220).
Figure 4 shows an enlarged view of said groove (220) of the lower region (210) of said molded base (200) previously seen in said Figures 1 to 3, in which said perpendicular walls (221), said shoulder (222), and said inclined surface (223) are brought to the evidence, in addition to a through opening (224), all visible from said groove (220), through which one of said lower ends (361) of said operating mechanism (300) can pass, after assembly (as seen in Figure 3). Furthermore, each of the shoulders (222) in a preferred embodiment has sharp corners. Said through opening (224) is placed longitudinally in its greatest extension to a "Y" axis of said circuit breaker (100) (Seen in Figure 2) and is capable of allowing the free passage of a said plurality of legs (330) of said operating mechanism (300) (seen in detail in Figure 5).
Figure 5 shows a perspective view of said operating mechanism (300) of said circuit breaker (100) according to the present invention, wherein said operating mechanism (300) is an electrical tripping mechanism preferably unipolar, bipolar, tripolar, tetrapolar, among others, commonly known by way of example, which comprises a plurality of side plates (310) placed on opposite sides of said operating mechanism (300), at least one protrusion (320), which projects in the upper portion, perpendicularly to said side plates (310), a plurality of legs (330), preferably four, which extend vertically downwards from each of said side plates (310), in which each said leg (330) comprises a proximal upper portion (340), an intermediate region (350) which is adjacent to the proximal upper portion (340), side tabs (351), comprising a lower edge (352), which form a right angle with the said side tabs (351), that protrude from the intermediate region (350), an upper outer edge of the side plates (310), a distal portion (360) that protrudes in the same direction and way as the proximal upper portion (340), lower ends (361), a plurality of grooves (370), each distributed between the distal portion (360) and the lower ends (361) of each leg (330), at least one handle mechanism (380) located in the upper region of said operating mechanism (300) and responsible for the internal movement of the interrupting components of said circuit breaker (100), a plurality of positioning latches (381) that protrude perpendicularly concerning the side plates (310), at least one main spring (382), at least one positioning shaft (383), at least one positioning hole (384), at least one return spring (385), at least one return shaft (386), at least one return hole (387), the elements (383, 384, 385, 386, 387) being placed aligned with the transverse axis "X" (seen in Figure 2) of said circuit breaker (100), and at least one said handle (388) (seen in Figure 11). Said perpendicular protrusion (320) may, e.g., have a cut and folded segment of the side plate (310) or a separate element fixed to the side plate (310) by means of welding and/or an adhesive and/or a screw and/or a rivet and/or other suitable fixation means. Said distal portion (360) has a thickness (362) (seen in Figure 6), preferably equal to the thickness of the leg (330), the side plate (310), and total length (363).
Figure 6 shows an enlarged partial view of said leg (330) of said operating mechanism (300) of Figure 5, where the region close to the upper edge (371) forms a portion or region fold in which a folding line (375) is formed, from which the distal portion (360) assumes the form and function of a tab (364), making it possible to promote the pivoting of said tab (364) and, thus, of at least one of said lower ends (361), around said folding line (375). The number of legs (330) may vary in position and quantity, depending on the design of said circuit breaker (100). Preferably, at least four said legs (330) are distributed around said operating mechanism (300), wherein each said leg (330) comprises a thickness (362) to be dimensioned according to the actuating forces, a total length (363) corresponding to the distance between said lower edge (352) and said lower ends (361), a tab (364) which is positioned in the middle or lower region of said legs (330), a width portion (365) determining the width of said tab (364), a through groove (370) in said thickness (362) and placed in the region of said tab (364), an upper edge (371), a lower edge (372), a left edge (373), a right edge (374), wherein the edge (371, 372, 373, 374), both equally opposed and preferably parallel to each other, and, consequently perpendicular to the upper (371) and lower (372) edge, which form a polygon, embodied by way of example, an imaginary folding line (375), which corresponds to the region where the fold of said legs (330) occurs and where said tab (364) is formed, a left horizontal edge (376), a right horizontal edge (377), an upper vertical edge (378), and a lower vertical edge (379), which delimit the location and dimensions of said groove (370) embodied by way of example.
Figures 7 and 8 present a cross-sectional side view of said circuit breaker (100) of Figure 1, showing the operating mechanism (300) fixed on the molded base (200) by introducing the legs (330) of said operating mechanism (300) into the grooves (224) of said molded base (200) (seen in Figure 4) and the folds of the tab (364) regions (seen in Figure 6) of said legs (330) of said operating mechanism (300), which are folded so as to position the grooves (370) on the shoulders (222) of said molded base (200), wherein said molded base (200) further comprises an angle (225) of inclined surface (223), and wherein additionally after introducing said legs (330) of said operating mechanism (300) and subsequent folding, a conformation angle (366), seen specifically in Figure 8, is provided to said regions of said tabs (364) of said legs (330). It can also be seen in Figure 8 that the positioning fold to be supplied to said regions of said tabs (364) of said legs (330) allows a fraction of said shoulders (222) of said molded base (200) to be introduced into said grooves (370). Additionally, lower edge (352) (seen in Figure 6) are provided for vertically touch abutment faces (not shown) of said molded base (200) to ensure the rigidly positioning of said operating mechanism (300) to said molded base (200) relative to the positioning of said grooves (370) on the shoulders (222) after a folding of said folding line (375) of said lower ends (361) of said distal portion (360) of said legs (330) of said operating mechanism (300). It can be seen in the section that this assembly allows for the limitation of a translation of said operating mechanism (300) on the "Y" and "Z" axis.
Figure 9 shows a lower perspective view of said molded cover (400) of said circuit breaker (100) of Figure 1, showing some of its internal details, wherein said molded cover (400) comprises a plurality of holes (410) and at least one vertical cutout (420).
Figure 10 shows a perspective view of the circuit breaker (100) of Figure 1 shown open, without its molded cover (400) or said cap (500), allowing to view into an upper opening of a molded base (200) a plurality of current path poles (230) comprising partition walls (231), a plurality of movable contacts (631), a plurality of fixed contacts (630), means of fixing connection terminals (640) of electrical connection, said operating mechanism (300) in the center and said handle (388), where said handle (388) of said circuit breaker (100) being capable of a translational movement on the "Y" axis in relation to the molded cover (400) and responsive with the driving movement of said elements (383, 384, 385, 386, 387) placed on the "X" axis of said circuit breaker (100) and in an internal rotary trajectory, on a rotating schematic axis "RX", so as to change the electrical conduction state of an electrical circuit between the "ON" and "OFF" states, mechanically driving the closing or opening of said plurality of f contacts (631) in relation to a plurality of fixed contacts (630) controlled by the operating mechanism (300) (seen in Figure 5), or to present another state, such as "tripping", for example, which represents an intermediate position, immediately after a circuit failure event, from a thermomagnetic or electronic set (not shown) of said circuit breaker (100).
Figure 11 shows a longitudinal cross-sectional side view of the region of the partition walls (231) (seen in Figure 10) of the circuit breaker (100) of Figure 1, showing at the lower part the molded base (200), above the molded cover (400), cap (500), in the center the operating mechanism (300), the vertical cutout (420), which presses and retains the perpendicular protrusion (320) of said operating mechanism (300) (also seen in Figure 5), limiting a translation of said operating mechanism (300) on the "Y" and "Z" axes.

Functioning of the invention

A circuit breaker (100) in accordance with the invention, comprises at least one molded base (200) that receives and houses at least one operating mechanism (300) and several other operating components, which can receive a electrical supply from conduction lines, having at least one current path pole (230) comprising at least one operating mechanism (300), a fixed contact (630), and at least one movable contact (631) of said circuit breaker (100), so as to interrupt an electrical circuit (seen in Figure 10), changing the electrical conduction state between "on" (ON) and "off' (OFF), in case of failure. Said circuit breaker (100) has at least one molded cover (400) placed on the molded base (200), and which closes the set and latches said operating mechanism (300) and may optionally have at least one cap (500) placed over said molded cover (400) and a handle (388).
The molded base (200) comprises at least one lower region (210) provided with at least two, preferably four grooves (220), which, in turn, each comprise at least one perpendicular wall (221) from which at least one shoulder (222) protrudes, at least one through opening (224) placed between said shoulder (222) and said inclined surface (223), through which one of the lower ends (361) of the operating mechanism (300) can pass, after an assembly between them (as seen in Figure 3).
The grooves (220) are open regions that can have any shape and several different sizes, as long as the combination of these allows the ends of instruments (punch, screwdriver or similar) can be introduced and moved at least partially inside the molded base (200) from said grooves (220), and the inclined surface (223) can be used for this purpose.
The perpendicular wall (221) is a surface that is adjacent to and is preferably perpendicular to the lower region (210) and preferably perpendicular to the projection of the shoulder (222), wherein said perpendicular wall (221) can serve as a stop for the tabs (364) of the legs (330) of the operating mechanism (300), as will be seen later.
The inclined surface (223) is situated on a surface opposite the perpendicular wall (221) and forms an inclined surface angle (225) with a value between 10° and 70°, preferably between 30° and 60° in relation to said inclined surface angle (225) of the circuit breaker (100).
The current path poles (230) are chambers that receive and bearing pivotally at least one movable contact (631) that is moved by driving the operating mechanism (300) to put the movable electrical contact (631) into contact or to interrupt it with at least one fixed contact (630), between one side of at least one connection terminal (640) and the other side of said at least one connection terminal (640) of an electrical circuit, on the side opposite to the circuit breaker (100). Furthermore, said current path pole (230) is normally adjacent to an electric arc extinguishing system (not shown), which aims to prevent damage to the equipment caused by the electric arc that forms when the electrical circuit is interrupted in operation resulting from said operating mechanism (300), particularly in the presence of high currents, as is the case with this type of device.
Although the preferential or expected condition is that the folding line (375) coincides with the upper edge (371), said folding line (375) should, in accordance with the invention, be understood as located in a region preferably adjacent to said upper edge (371), and may therefore coincide or not with said upper edge (371).
In a preferred embodiment, the groove (370) is positioned in the vicinity of the distal portion (360) so that the left edge (373) and right edge (374) have, respectively, a left horizontal edge (376) and a right horizontal edge (377) in relation to the corresponding left and right edges of the tab (364), and so that the upper edge (371) and lower edge (372) have, respectively, a said upper vertical edge (378) and a said lower vertical edge (379) in relation to at least one of the lower ends (361).
Although the preferred shape of the groove (370) is the polygonal shape, more preferably the straight polygonal shape, it should be noted that said groove (370) can assume other shapes such as, for example, the circumferential, ellipsoidal, cylindrical shapes, among others, and one or more said grooves (370) of the same said operating mechanism (300) can also have geometries that are the same or different from each other. It should also be noted that said grooves (370) can be either cutouts, through holes, or depressions or low-relief polygons formed by punching or crushing.
The left horizontal edge (376) and the right horizontal edge (377) each correspond to a value between 5 and 40%, preferably between 10 and 30% of a width portion (365) of the tab (364). Although said horizontal edges (376, 377) should preferably be equal to each other, for the purposes of horizontal centering of the groove (370) in relation to the width portion (365) of said tab (364), said horizontal edges (376, 377) may be different from each other, depending on the design and construction characteristics of said circuit breaker (100).
The thickness (362) and width portion (365) must be equal to or, preferably, smaller than the corresponding dimensions of the through openings (224), so as to allow the tabs (364) of the operating mechanism (300) to pass through said through openings (224) and remain entirely housed inside the molded base (200), the vertical movement of insertion of said operating mechanism (300) being preferably limited by the lower edge (352), which may vertically touch lower abutment faces (not shown) of said molded base (200).
The lower vertical region (379) corresponds to a value between 5 and 45%, preferably between 10 and 35% of the total length (363) of the distal portion (360).
The handle mechanism (380) comprises at least a positioning latch (381), a main spring (382), a positioning shaft (383), a positioning hole (384), a return spring (385), a return shaft (386), a return hole (387), and a handle (388), wherein said handle mechanism (380) is the mechanism responsible for driving internal interrupt trigger components of the current path pole (230) of the circuit breaker (100).
The positioning latches (381) are latches located internally in the operating mechanism (300) and actuate as stops, which limit the shift of the handle mechanism (380) to a "closed position", so as to ensure that said contacts (630, 631) remain in contact with each other.
The main spring (382) is a spring located internally in the operating mechanism (300) and has the function of keeping the handle mechanism (380) engaged in a "closed" or armed position, wherein said main spring (382) pulls said handle mechanism (380) downwards, displacing all the elements of said handle mechanism (380), so as to result in the shift of the fixed and movable electrical contacts (630, 631), which are pressed against each other as a consequence.
The positioning shafts (383) are axes that serve as fixed support for the mechanical transmission of the internal rotating elements of said circuit breaker (100), which aim to enable the internal movement of these rotating elements.
The positioning holes (384) are holes that receive the positioning shafts (383) and are distributed across the operating mechanism (300), actuating as a support for the transmission of forces associated with the rotation of the internal components of said operating mechanism (300).
The return spring (385) is a spring that aims to assist in returning the handle mechanism (380) to an "open position", in addition to preventing it from accidentally entering a "closed position" without an outer driving force performed by a user to drive the circuit breaker (100).
The return shaft (386) and the return hole (387) are elements that aim to receive, and hold said return spring (385) fixed, being distributed in quantities corresponding to each other.
The handle (388) is an electrical switch driver capable of alternating, by means of an outer driving force performed by a user, the handle mechanism (380) of the operating mechanism (300) of the circuit breaker (100), freely between a closed position and an open position. Preferably, if there is only one said handle (388), it is preferably centered in relation to the molded cover (400) and/or in relation to the cap (500) of said circuit breaker (100) as acknowledged by the person skilled in the art, but should not be a limiting factor of the present invention, since said operating mechanism (300) can use the same technique, and the same technical effect obtained, if said handle (388) is displaced in relation to the center of said circuit breaker (100). If there are two or more said handles (388), they are preferably placed next to each other and normally in a central position in relation to said molded cover (400) and/or in relation to said cap (500) of said circuit breaker (100).
The fixation of the operating mechanism (300) to said molded base (200) occurs through the conformation of said distal portions (360) of the legs (330) at their respective folding lines (375), forming tabs (364), which plastically deform at a conformation angle (366) so as to house the grooves (370) in the shoulders (222). The conformation angle (366) corresponds to a value between 1 and 90°, preferably between 20 and 45° with respect to the vertical axis or with respect to the plane of said legs (330) of said operating mechanism (300). Preferably said conformation angle (366) is achieved by having said legs (330) of said operating mechanism (300) folded so that the dimension of the lower ends (361) is greater than the dimension of the pair of side plates (310) of said operating mechanism (300). In another manner, the conformation angles (366) of said legs (330) of the operating mechanism (300) are folded so that the dimension of the lower ends (361) is smaller than the dimension of the pair of side plates (310) of said operating mechanism (300).
More specifically, the fixation of the operating mechanism (300) to the molded base (200) occurs by introducing the tabs (364) of the legs (330) of said operating mechanism (300) into the through openings (224) of the molded base (200), until an alignment of the grooves (370) of said operating mechanism (300) occurs in the shoulder (222) of said molded base (200), this alignment occurs when the respective lower edge (352) vertically touches said abutment faces (226) of said molded base (200).
After aligning the grooves (370) in the shoulder (222), preferably an instrument (not shown) is inserted into the groove (220) which, in turn, presses and deforms the lower ends (361) of the tabs (364) of the legs (330) of the operating mechanism (300) until said lower ends (361) of said operating mechanism (300) abut against the perpendicular wall (221) of said molded base (200).
Optionally, the inclined surface (223) can be used as a support to direct and assist an instrument, such as a rod, while it presses and deforms the lower ends (361) of the tabs (364) of the legs (330) of the operating mechanism (300), until said lower ends (361) of said operating mechanism (300) abut against said perpendicular wall (221) of the molded base case (200).
Furthermore, optionally, depending on the size of the lower vertical edge (379), the lower ends (361) of the operating mechanism (300) may not touch said perpendicular wall (221) of the molded base (200). However, the value of the conformation angle (366) should preferably be maintained to ensure the fixation of said operating mechanism (300), having a limitation given by lower edge (352) of said operating mechanism (300) as a counterpoint, which can vertically touch lower abutment faces (not shown) on the molded base (200). Subsequently, by means of the deformation of the tabs (364), this so-called latching limitation occurs in two degrees of freedom. More precisely, this achieves one of the objectives of the invention, wherein the locking occurs at the angular encounter between the groove (370) and the surface of the shoulder (222), impeding a translation of said operating mechanism (300) on the X and Y axes (see Figure 8).
In a preferred embodiment of the present invention, the fixation of the operating mechanism (300) is achieved by means of the deformation of the tabs (364) at the angular encounter between the groove (370) and the surface of the shoulder (222), at least one pair of said tabs (364) of the legs (330) of said operating mechanism (300) being deformed in an inverted way in such a manner that, when a set of forces actuate trying to extract in a concentrated manner one of said tabs (364) from within the through opening (224) of the molded base (200) of said circuit breaker (100), at least one of said tabs (364) on the opposite side counters it by blocking said groove (370) and the other opposite surface of said shoulder (222) from within the other said through opening (224) of said molded base (200) of said circuit breaker (100). This opposition geometry contributes significantly to carrying out intermediate operating tests, which can be performed without the presence of the molded cover (400) and even critical tests subjected to driving forces.
As above mentioned and due to the opposition geometry, the present invention also achieves one of the proposed objectives of not deforming the molded base (200) or preventing the use of fixation means such as screws, reinforcement washers, pins, and equivalent fixation elements dedicated to fixation the operating mechanism (300) to said molded base (200), due to the preferred embodiment of the present invention of promoting a controlled deformation of at least one pair of tabs (364), of at least one pair of legs (330) of said operating mechanism (300), requiring a reduced folding force, resulting from the presence of the grooves (370) and which does not deform or reduces deformations of said molded base (200).
Furthermore, the present invention achieves one of the proposed objectives, wherein, if any component of the operating mechanism (300) of the circuit breaker (100) presents any malfunction, it can easily be replaced during maintenance, since the operating mechanism (300) does not require any means of mobile or permanent connection, which guarantees additional speed and ease in replacing this element.
It should be noted that the molded cover (400) has assembly dimensions corresponding to those of the molded base (200), so as to allow a corresponding fit between them, sealing and protecting the inside of the circuit breaker (100), wherein said molded cover (400) comprises at least one vertical cutout (420) and a plurality of holes (410).
In a step subsequent to the tests, in order to doubly increase the robustness of the fixation in the final operation of the circuit breaker (100), on the upper part of the operating mechanism (300), a molded cover (400) can be provided, wherein the lower area of said molded cover (400) can additionally press the perpendicular protrusion (320) of said operating mechanism (300) to a defined position, increasing the three-dimensional stability of the assembled set of said circuit breaker (100).
The holes (410) are through holes and preferably receive fasteners, movable joining means, such as, for example, screws, rivets, or pins that pass through both the molded cover (400) and the molded base (200), so as to keep both elements joined and fixed to each other.
Another additional objective achieved with the present invention is that the vertical cutout (420) of the molded cover (400) additionally supports and retains the perpendicular protrusion (320) so as to firmly clamp the operating mechanism (300) to the molded base (200) so as to impede its translation and rotation. Latching is achieved in two degrees of freedom, impeding a translation of said operating mechanism (300) on the Y and Z axes (see Figure 11). This latching complements the mechanical resistance of the fixation of said operating mechanism (300) already reinforced by the angular encounter between the groove (370) and the surface of the shoulder (222) of at least one pair of tabs (364) of said distal portions (360) of the legs (330) in their respective folding lines (375), deformed in an inverted way in the assembly of said operating mechanism (300) with said molded base (200).
The cap (500) is additionally fixed to the upper part of the molded cover (400), and may commonly contain information or instructions such as, for example, a position of said handle (388) that turns said circuit breaker (100) on and off, in addition to information such as voltage and current of said circuit breaker (100) printed, glued or stamped onto its outer face. Another function is to allow outer access to the upper part for maintenance of internal components of the said circuit breaker (100).
Optionally, it is possible for the circuit breaker (100) not to have the cap (500), so that the closing of said circuit breaker (100) results only from the fixation of the molded base (200) to the molded cover (400). In this case, the circuit breaker (100) information may be printed, glued or stamped onto the outer face of said molded cover (400) or said molded base (200), without prejudice to the present invention.
The contacts (630, 631) are internal switching elements that aim to (i) allow the passage of electrical energy when they are in contact with each other; or (ii) interrupt the passage of electrical energy when they are not in contact with each other.
In both cases, each fixed contact (630) remains fixed with an electrical connection terminal (640), comprising a movable fixation means, such as a screw, which secures a current path pole (230) of an electrical circuit in the circuit breaker (100).
Furthermore, when a fault occurs, notably an overload or short-circuit, the contacts (630, 631) are designed with the main function of opening automatically, due to the action of any of the electrical tripping devices of the state of the art, which actuate together with the operating mechanism (300). In this way, said open contacts (630, 631), together with the electric arc extinguishing system (not shown) and other circuit breaker construction components, such as cables, terminals, contact system, etc., present herein and in the state of the art, are capable of preventing damage to electrical equipment connected to the circuit breaker (100).
The preferred method of assembling the operating mechanism (300) on the molded base (200) of the present invention comprises the steps of:

I. introducing a plurality of tabs (364) of a plurality of legs (330) of said operating mechanism (300) into a plurality of through openings (224) of a molded base (200);
II. aligning a plurality of grooves (370) of a tab (364) of said operating mechanism (300) with the respective at least one pair of shoulders (222) of said molded base (200);
III (a). pressing and deforming folding lines (375) of a tab (364) of the ends of the legs (330) of said operating mechanism (300), until said legs (330) reach a conformation angle (366); or
III (b). until said legs (330) reach a said conformation angle (366) and the lower ends (361) of the operating mechanism (300) can touch a perpendicular wall (221) of said molded base (200);
IV. housing said grooves (370) in said shoulders (222);
V. positioning at least one vertical cutout (420) of said molded cover (400) over a perpendicular protrusion (320) of said operating mechanism (300); and
VI. firmly fix the vertical cutout (420) of said molded cover (400) to the perpendicular protrusion (320) preferably using joining means through a plurality of holes (410).

As an additional detail, it is worth mentioning that the terms "closed position" and "open position" serve to describe the electrical circuit of said circuit breaker (100), where the "closed position" denotes a closed electrical circuit, which allows the passage of electrical current through the contact of said fixed and mobile contacts (630, 631) and the "open position" denotes an open electrical circuit, which does not allow the passage of electrical current through said fixed and mobile contacts (630, 631), since they are situated apart from each other in this position.

Final remarks

The present invention describes a circuit breaker (100) comprising a molded base (200), an operating mechanism (300), a molded cover (400), and, optionally, a cap (500), wherein shoulders (222) of a molded base (200) are housed in grooves (370) of said operating mechanism (300) after an assembly with each other, so as to allow said operating mechanism (300) to be fixed to said molded base (200) without the use of screws, reinforcement washers, pins, and equivalent fixation elements dedicated or exclusive for fixation said operating mechanism (300) inside said molded base (200).
It is evident that the measurements and relationships between dimensions described for the present invention may vary according to the dimensioning of the molded base (200), the operating mechanism (300), the molded cover (400) and the cap (500). However, these measures and their relationships are highly reliable and reproducible, in addition to being highly efficient and effective.

Conclusion

As can be inferred from the description above, the object, according to the present invention, surpasses the solutions provided for by the state of the art, being an object perfectly susceptible to industrial application, which presents novelty and non-obviousness.

Claims

A circuit breaker (100) comprising a molded base (200), an operating mechanism (300) together with a separable pair of contacts (630, 631) and a molded cover (400), wherein:
the molded base (200) comprises a plurality of grooves (220), a plurality of shoulders (222), a plurality of through openings (224); and

said operating mechanism (300) comprises a plurality of side plates (310), at least one perpendicular protrusion (320), and a plurality of legs (330);

characterized in that each leg (330) comprises a tab (364) comprising folding lines (375), and wherein said tab (364) can be inserted into said through openings (224) of at least one pair of grooves (220) of said molded base (200) and be folded so as to position at least one pair of grooves (370) on shoulders (222) of said molded base (200) of said circuit breaker (100).
The circuit breaker (100) according to claim 1, characterized in that the folding line (375) is provided in the vicinity of a lower end (361) of said leg (330).
The circuit breaker (100) according to claim 1, characterized in that a folding line (375) is provided in the vicinity of said groove (370).
The circuit breaker (100) according to claim 1, characterized in that said legs (330) of the operating mechanism (300) are folded so that the dimension of the lower ends (361) is greater than the dimension of the pair of side plates (310) of said operating mechanism (300).
The circuit breaker (100) according to claim 1, characterized in that said legs (330) of the operating mechanism (300) are folded so that the dimension of the lower ends (361) is smaller than the dimension of the pair of side plates (310) of said operating mechanism (300).
The circuit breaker (100) according to claim 1 or 2, characterized in that the molded base (200) further comprises an inclined surface (223).
The circuit breaker (100) according to claim 6, characterized in that the inclined surface (223) is situated on a surface opposite the perpendicular wall (221) and forms an inclined surface angle (225) with a value between 10° and 70°, preferably between 30° and 60°, in relation to said inclined surface angle (225) of the circuit breaker (100).
The circuit breaker (100) according to any one of claims 1 to 7, characterized in that at least one leg (330) of the operating mechanism (300) further comprises a proximal upper portion (340), an intermediate region (350) and at least one side tab (351).
The circuit breaker (100) according to any one of claims 1 to 8, characterized in that at least one leg (330) of the operating mechanism (300) further comprises a distal portion (360) and a total length (363).
The circuit breaker (100) according to any one of claims 1 to 9, characterized in that at least one leg (330) of the operating mechanism (300) further comprises a conformation angle (366).
The circuit breaker (100) according to any one of claims 1 to 10, characterized in that if further comprises a left horizontal edge (376), a right horizontal edge (377), an upper vertical edge (378) and a lower vertical edge (379).
A method of assembling an operating mechanism (300) on a molded base (200) of a circuit breaker (100), characterized by the steps of:
I. introducing a plurality of tabs (364) of a plurality of legs (330) of an operating mechanism (300) into a plurality of through openings (224) of a molded base (200);

II. aligning a plurality of grooves (370) of the operating mechanism (300) into a respective plurality of shoulders (222) of said molded base (200);

III (a). pressing and deforming, at their respective folding lines (375), the ends of said legs (330) of said operating mechanism (300), until said legs (330) reach a conformation angle (366); or

III (b). pressing and deforming, at their respective folding lines (375), the ends of the legs (330) of the operating mechanism (300), until these legs (330) reach a conformation angle (366) and the free lower ends (361) of the operating mechanism (300) touch the perpendicular wall (221) of the molded base (200); and

IV. housing the grooves (370) in the shoulders (222).
The method of assembling an operating mechanism (300) on a molded base (200) of a circuit breaker (100) according to claim 12, characterized in that it further comprises the steps of:
V. positioning at least one vertical cutout (420) of a molded cover (400) on a perpendicular protrusion (320); and

VI. firmly fixation the vertical cutout (420) to the perpendicular protrusion (320) using fixation means through a plurality of holes (410).