Handgrip for electrical molded case circuit breaker and circuit breaker unit comprising said handgrip

Abstract

 Handgrip (20, 30) which can be associated to an electrical molded case circuit breaker (1), the breaker comprising at least one first unit of electrical connection terminals (6) and comprising a box-type casing (2) provided with at least one first plurality of recesses (9) for housing said electrical terminals (6), each recess being provided with an open end portion (10) on a front face (3) of the box-type casing (2), the handgrip (20, 30) comprising a gripping organ (21, 31) intended to project from the main casing (2) in order to facilitate manual grasping of the breaker (1);
The handgrip (20,30) further includes an array of protective elements (22) in insulating material, each such as to engage with a corresponding recess (9) in order to prevent access to the connection terminal (6) through said open end portion (10).

Description

[0001] The present invention relates to the technical sector of electrical circuit breakers and in particular it relates to a handgrip for an electrical molded case circuit breaker.

[0002] To facilitate operations of installing and removing a circuit breaker in an electricalal panel, the use of ergonomic removable handling means is known, which can be associated to a breaker or provided as an integral part of the molded case circuit breaker, making it easier to grasp manually. Said handling means are produced in the form of handles or knobs protruding from the molded case and are generally made in insulating material.

[0003] The object of the present invention is to provide a handgrip that can be associated to a molded case circuit breaker which, besides facilitating manual grasping of the breaker, is also such as to prevent dangerous access to the electricalally conductive and exposed parts of the circuit breaker.

[0004] Said object is reached by means of a handgrip as defined in the attached claim 1 in general and in preferred embodiments as defined in the dependent claims.

[0005] A further object of the present invention is a circuit breaker unit as defined in the attached claim 13.

[0006] Further features and advantages of the present invention will become more apparent from the following detailed description of an exemplary but non-limiting embodiment thereof, as illustrated in the accompanying drawings, in which:

• figure 1 shows an axonometric projection of a preferred embodiment of an unassembled circuit breaker unit including a handgrip according to the present invention;
• figure 2 shows an axonometric projection of the handgrip in figure 1;
• figure 3 shows an axonometric projection of a circuit breaker unit with a handgrip assembled and a handgrip not assembled; and
• figure 4 shows a front view of the circuit breaker unit in figure 1, assembled and comprising two handgrips according to the present invention.

[0007] In the figures, the same or similar elements will be indicated with the same reference numbers.

[0008] With reference to the attached drawings, a circuit breaker unit is shown comprising a handgrip according to a preferred embodiment of the present invention.

[0009] The circuit breaker unit comprises a molded case circuit breaker 1, for example a three-pole circuit breaker with thermal and magnetic protection.

[0010] A molded case circuit breaker, as opposed to a circuit breaker of the so-called "air" type, has a box-type casing 2 generally parallelepiped and made of insulating material, which acts as support for the mechanisms inside the circuit breaker. At present, molded case circuit breakers are generally used in the industrial automation and advanced tertiary sectors for interrupting currents for example with values up to 1500 A.

[0011] The front face 3 of the box-type casing 2, having a substantially quadrangular shape, is provided with an opening through which a rotating lever 4 passes for controlling the circuit breaker 1.

[0012] On one upper horizontal face 2 of the box-type casing 2, a first group of three terminals for electrical connection 6 is provided, for connecting the circuit breaker 1 to an electrical circuit outside the breaker 1, for example to an electrical circuit upstream of the breaker 1. A similar group of electrical connection terminals 8 is provided on one lower horizontal face 7 of the box-type casing 2, for connecting the breaker 1 to an electrical circuit outside the breaker 1, for example downstream of the breaker 1.

[0013] The electrical terminals 6 are at least partially housed in respective recesses 9 provided in the box-type casing 2 near the upper face 5. In the embodiment described, said recesses 9 house a substantially plate-shaped end portion of the electrical terminals 6. In the particular embodiment described, the electrical terminals 6 have a conductive bar perpendicular to the plate-shaped end portion and have an opposite rounded end portion, such as to be engaged with a corresponding connection terminal provided in a control panel or insertion board. As can be seen in figure 3, the conductive bar of the terminals 6 juts out from the horizontal face 5 projecting towards the rear face 34 of the box-type casing 2. In an alternative embodiment, the connection terminals 6 could be common screw terminals housed in the recesses 9 and such as to be connected to cable conductors for connection of the breaker 1 to an external circuit.

[0014] Each housing recess 9 is provided with an open end portion 10 on the front face 3 of the box-type casing 2.

[0015] Similar housing recesses, not visible in the drawings, are provided in the box-type casing 2 near the lower horizontal face 7 for housing, at least partially, the other electrical terminals 8 of the breaker 1. Said recesses are also provided with an open end portion 11 on the front face 3 of the box-type casing 2 of the breaker 1. As far as the connection terminals 8 are concerned, the same applies as that described for the connection terminals 6.

[0016] In a particularly preferred embodiment, the housing recesses 9 have one open side on the upper horizontal face 5 of the box-type casing 2. Similar open sides are provided in the recesses, not visible, arranged on the lower horizontal face 7.

[0017] A handgrip 20, 30 is associated to the breaker 1, conveniently made of electrically insulating material and comprising a gripping organ 21, 31 intended to project from the main casing 2 of the associated breaker 1, to facilitate manual grasping of the breaker 1.

[0018] Advantageously, the handgrip 20, 30 comprises an array of protective elements 22 in insulating material. Each of said protective elements 22 is such as to be engaged with a corresponding recess 9 of the box-type casing 2 so as to prevent dangerous access to the connection terminal 6 through the open end portion 10 of the recess 9. In a particularly preferred embodiment, as shown in the attached drawings, the protective elements 22 are made in the shape of bars having a substantially disc-shaped end portion.

[0019] Preferably, each protective element 22 can be engaged with the respective recess 9 by axially crossing through the open end portion 10 of said recess 9, as indicate by the arrow IV in figure 1. Axial direction means a direction perpendicular to the front face 3 of the box-type casing 2 of the breaker 1.

[0020] Preferably, the handgrip 20, 30 comprises a bar 23 at the base of the gripping organ 21. Said bar 23 extends transversally compared to the axial direction of the recesses 9 and the array of protective elements 22 juts out from the bar 23 on the opposite side from the gripping organ 21, 31.

[0021] As can be seen better in figure 2, in a particularly advantageous embodiment, the handgrip is essentially made of two distinct and combinable pieces 20, 30, shown disassembled in said figure. In particular, the handgrip comprises a front piece 20 comprising the array of protective elements 22 and a rear piece 30 essentially "L" shaped and including:

• a first part 32, substantially plate-like, intended to be removably juxtaposed to a rear face 34 of the box-type casing 2;
• a second part 35, at right angles to the first part 32, and having a first end portion connected to the first part 32 and an opposite end portion intended to interact with the front piece of the handgrip 20.

[0022] The first part 32 of the rear piece of the handgrip 30 is, for example, provided with one or more openings 36 to permit fixing, by means of screws, the rear piece 30 to the rear face 34 of the box-type casing 2. In a particularly preferred embodiment, the second part 35 of the rear piece of the handgrip 30 comprises guided coupling means 38, for coupling the rear piece 30 to the horizontal face 5 of the box-type casing 3, interacting with combined guided coupling means 39 provided in the box-type casing 2 on the horizontal face 5. In the embodiment described, the guided coupling means 38 comprise at least one cursor 38 which slides into a respective counter-shaped slot 39 provided in the box-type casing 2 (figure 1). The cursor 38 is preferably made with a dovetail section so as to firmly engage the first part 35 of the rear piece of the handgrip 30 to the horizontal face 5. The arrow V in figure 1 indicates the direction and insertion direction of the cursors 38 into the slots 39.

[0023] In a particularly advantageous embodiment, the second part 35 of the rear handgrip piece 30 is such as to be juxtaposed to the horizontal face 5 in order to prevent any possible access to the terminals 6 from the side of the horizontal face 5. For this purpose, the second part 35 of the rear handgrip piece 30 preferably includes a plurality of grooves 40, each defining a slot with insulating walls intended to receive a respective terminal bar 6 or, alternatively, a terminal cable, coming out from the horizontal face 5. More preferably, the grooves 40 terminate with an end portion 41 facing the rear face of the box-type casing 2 which is open so it can be crossed by a terminal bar 6, or terminal cable. In the case where the end portion 41 is intended to be crossed by a terminal bar 6, it is possible to provide an insulating and projecting collar 42 such as to be received in an opening which accesses the terminal into which the terminal 6 is to be inserted. Obviously, in this case, end portions of terminals 6 must be provided which project beyond said collar 52, so that the electrical connection can be made between the terminal 6 and a corresponding terminal, provided for example in an insertion board.

[0024] As can be seen in figure 2, in a non-limiting preferred embodiment, the gripping organ 21, 31 is essentially shaped like a trapezoidal plate and comprises two juxtaposed plates provided in the front piece of the handgrip 20 and in the rear piece of the handgrip 30 respectively. By uniting the front piece 20 and the rear piece 30, for example by means of combined interlocking joints 45, 46, 46, 47 distributed between the front piece 20 and the rear piece 30, the two plates form a single plate 21, 31 projecting from the casing 2 of the circuit breaker 1 and such as to facilitate manual grasping of the breaker. In addition to the combined interlocking joints 45, 46, 46, 47, further removable fixing means can optionally be provided in order to ensure safe coupling of the two pieces 20, 30 of the handgrip, such as screws, bolts and similar.

[0025] In a particularly advantageous embodiment, the handgrip 20, 30 can further be provided with centering and guiding means, for example a pair of projecting fins 50, such as to facilitate the insertion of a circuit breaker into an insertion board provided with combined insertion and guiding means, for example in the form of guiding grooves, not shown in the drawings, and such as to interact with a respective fin 50.

[0026] As can be observed in figure 4, in a preferred embodiment, it is particularly convenient to associate a pair of handgrips of the type described above to the two opposing sides of the box-type casing of the circuit breaker 1.

[0027] As is evident from the above description, a handgrip according to the present invention makes it possible to entirely satisfy the above-described requirements with reference to the prior art. In particular, a handgrip according to the present invention facilitates and makes safe the operations of installation/removal of the circuit breaker, also preventing access to the exposed conductive parts of the circuit breaker when the breaker is installed and fed.

[0028] Naturally, in order to satisfy contingent and specific requirements, a person skilled in the art may apply to the above-described handgrip according to the invention many modifications and variations, all of which, however, are included within the scope of protection of the invention as defined by the following claims.

Claims

1. Handgrip (20, 30) which can be associated to an electrical molded case circuit breaker (1), the breaker comprising at least one first unit of electrical connection terminals (6) and comprising a box-type casing (2) provided with at least one first plurality of recesses (9) for housing said electrical terminals (6), each recess being provided with an open end portion (10) on a front face (3) of the box-type casing (2), the handgrip (20, 30) comprising a gripping organ (21, 31) intended to project from the main casing (2) in order to facilitate manual grasping of the breaker (1);
characterized in that
the handgrip (20,30) further includes an array of protective elements (22) in insulating material, each such as to engage with a corresponding recess (9) in order to prevent access to the connection terminal (6) through said open end portion (10).

2. Handgrip (20,30) according to claim 1, wherein each protective element (22) can be engaged axially with the open end portion (10) of a respective recess (9).

3. Handgrip (20,30) according to claim 1, wherein the handgrip includes a bar (23) at the base of the gripping organ (21,31), said bar extending transversally compared to axial direction of the housing recesses (9), the array of protective elements (22) projecting from the bar (23) from the side opposite the gripping organ (21,31).

4. Handgrip (20,30) according to claim 3, wherein the protective elements (22) comprise an end portion distal from the bar (23) which is essentially disc-shaped.

5. Handgrip (20,30) according to any of the previous claims, wherein the handgrip is essentially made in two distinct and combinable pieces (20, 30), of which a front handgrip piece (20) comprising the array of protective elements (22) and a rear handgrip piece (30) essentially "L" shaped and including:

- a first part (32) substantially plate-like and intended to be juxtaposed to a rear face (34) of the box-type casing (2);

- a second part (35), at right angles to the first part (32), and having a first end section connected to the first part (32) and an opposite end portion intended to interact with the front handgrip piece (20).

6. Handgrip (20,30) according to claim 5, wherein the housing recesses (9) have one open side on a lateral face (5,7) of the box-type casing (2) and wherein the connection terminals (6) comprise bars or cables projecting outside the box-type casing (2) and which extend parallel to said lateral face (5,7) towards the rear face (34), the second part (35) of the rear handgrip piece (30) being such as to be juxtaposed to the lateral face (5) in order to prevent access to said bars or cables from said lateral face (5).

7. Handgrip (20,30) according to claim 6, wherein the second part (35) of the rear handgrip piece (30) includes a plurality of grooves (40), each defining a slot such as to receive a respective projecting bar or cable.

8. Handgrip (20,30) according to claim 7, wherein the grooves terminate with an open end portion (41) facing the rear face of the circuit breaker, in such a way that said rear handgrip piece (32) can be crossed by said bars or cables.

9. Handgrip (20,30) according to any of the previous claims from 5 to 8, wherein the gripping organ comprises two juxtaposed plates (21,31) provided in the front handgrip piece (20) and in the rear handgrip piece (30) respectively.

10. Handgrip (20,30) according to any of the previous claims from 6 to 9, wherein the second part (35) of the rear handgrip piece (30) comprises guided coupling means (38), for coupling the rear piece (30) to said lateral face (5) of the box-type casing (2), interacting with combined guided coupling means (39) provided in the box-type casing (2) on said lateral face (5).

11. Handgrip (20,30) according to claim 10, wherein said guided coupling means comprise at least one cursor (38) with a dovetail section.

12. Handgrip (20,30) according to any of the previous claims, the handgrip further comprising guided centering means (50) such as to facilitate insertion of the circuit breaker (1) into an insertion board provided with combined insertion and guiding means.

13. Circuit breaker unit (1,20,30), comprising a molded case circuit breaker (1) and at least one handgrip (20,30) according to any of the previous claims.

Drawing