EP4035228A1

EP4035228A1 - Fuse-comprising circuit-breaking apparatus

Info

Publication number: EP4035228A1
Application number: EP20772329.7A
Authority: EP
Inventors: Arnaud COULON
Original assignee: Mersen France SB SAS
Current assignee: Mersen France SB SAS
Priority date: 2019-09-24
Filing date: 2020-09-23
Publication date: 2022-08-03
Also published as: WO2021058517A1; FR3101192B1; FR3101192A1

Abstract

A fuse-comprising circuit-breaking apparatus, comprising: - a casing comprising at least one housing for receiving a fuse; and - at least one electrical connector (10) that is associated with said housing with a view to connecting an end terminal of a fuse when this fuse is inserted into the receiving housing; characterised in that the electrical connector (10) comprises a base segment (22) and a plurality of first contact fingers (24) and of second contact fingers (24') that are arranged in succession along the base segment, in alternation on either side of a median geometric plane of the base segment (22), so as to define a longitudinal receiving region for accommodating the terminal.

Description

TITLE: Electrical fuse cut-off device

The present invention relates to a fused electrical switching device.

In the field of electrical distribution, it is known to use electrical switching devices comprising one or more fuses, such as fuse switch-disconnectors, to protect an electrical installation.

Such a device generally comprises one or more removable fuse cartridges connected between input and output terminals of the device.

In order for the fuses to play their role safely, it is necessary that the electrical connection between the terminals of the fuse and the device is correctly made in all circumstances, using appropriate electrical connectors. These connectors must be simple to manufacture, so as not to unnecessarily increase the cost of manufacturing the device.

There is therefore a need for a fused electrical switching device, such as a fuse switch-disconnector, comprising an improved electrical connector.

To this end, one aspect of the invention relates to a fused electrical switching device, comprising:

- a housing comprising at least one housing for receiving a fuse; and

- at least one electrical connector associated with said housing for connecting an end terminal of a fuse when this fuse is inserted into the receiving housing.

The electrical connector comprises a base portion and a plurality of first contact fingers and second contact fingers arranged in succession along the base portion, alternately on either side of a median geometric plane of the portion. base, so as to delimit a longitudinal reception area to accommodate the terminal.

Thanks to the invention, the electrical connector enables good contact with the connection terminal of the fuse, while being simple to manufacture.

According to advantageous but not compulsory aspects, such a breaking device can incorporate one or more of the following characteristics, taken in isolation or in any technically admissible combination:

- The contact fingers have identical dimensions.

- Each contact finger has a straight portion configured to come into direct contact with the fuse terminal.

- The electrical connector is made of a metallic material. - At least part of the first contact fingers and of the second contact fingers has an upper part flared outwards from the central reception zone.

- The first contact fingers and the second contact fingers are connected to the base portion by a curved lower part which moves away from the base portion.

- The electrical connector is electrically connected to an electrical connection element of the disconnector through the base portion.

- The connector comprises an elastic return element associated with the first contact fingers and the second contact fingers.

- The first contact fingers and the second contact fingers have a groove in which the elastic return member is received.

- Each reception housing has at least two such electrical connectors.

The invention will be better understood and other advantages thereof will emerge more clearly in the light of the following description of an embodiment of an electrical switching device with a fuse, given solely by way of example and made with reference to the accompanying drawings, in which:

[Fig 1] Figure 1 schematically shows a fuse electrical switching device in a front view;

[Fig 2] Figure 2 schematically shows an electrical connector of the switchgear of Figure 1 according to embodiments of the invention;

[Fig 3] Figure 3 shows schematically, in close-up view, part of an electrical connector similar to that of Figure 2 and further comprising an elastic return member according to embodiments of the invention.

Figure 1 illustrates an electrical switching device 2 with fuses, such as a fused switch-disconnector.

For example, the device 2 makes it possible to protect an electrical installation thanks to one or more removable fuse cartridges each configured to interrupt an electric current when the latter has an excessively high current, for example due to an electrical fault in the installation. The fuses are removable and can be disconnected by a user using an appropriate mechanism to interrupt the flow of current.

The apparatus 2 comprises a housing 4 made of an electrically insulating material, such as a polymer, for example molded plastic. The housing 4 comprises one or more housings 6a, 6b, 6c each configured to receive a fuse cartridge 8 (simply called “fuse” in what follows).

For example, the housings 6a, 6b, 6c are delimited inside the housing 4 by internal partitions, which can be formed integrally with the outer body of the housing 4.

According to embodiments, the housing 4 has a rectangular shape and the housings 6 are aligned vertically one above the other.

In the example illustrated, the device 2 is connected with a three-phase installation and can thus receive three fuses 8, each being associated with an electrical phase of the electrical installation.

Alternatively, the device 2 could be modified to operate with an electrical installation comprising a different number of phases, such as a single-phase electrical installation.

Preferably, each fuse 8 has a main body and two upstream and downstream connection terminals 20 extending outside the body.

For example, the main body has the shape of a block or a cylinder.

The terminals 20 each have a blade or rod shape and extend on either side of the main body in the same longitudinal direction.

For example, fuses 8 are low voltage fuses as described in standard IEC / EN 60269-2-1.

According to examples given by way of illustration, the fuses 8 are fuse cartridges of the DIN NH type, also called "knife-edge fuses".

According to embodiments, to facilitate the insertion and removal of the fuse cartridges 8, the apparatus 2 may comprise, for each housing 6a, 6b, 6c, a cradle mounted to pivot relative to the housing 4 and configured to hold a cartridge fuse 8, for example by means of a fixing device. These cradles are not illustrated in figure 1.

For example, each cradle is movable between an open position, allowing the insertion or removal of the fuse 8, and a closed position, in which the fuse 8 is received inside the corresponding housing. The cradles can be mechanically linked together by an appropriate linkage mechanism, such as one or more levers, so that the opening and closing movements are simultaneous between all the cradles of the device 2. The apparatus 2 also comprises a plurality of electrical connectors 10 for connecting the fuses 8 to the electrical installation. In practice, each housing 6 is associated with a pair of upstream and downstream electrical conductors 10.

The connectors 10 are used to connect the upstream and downstream terminals of each fuse 8 with a corresponding electric line of the electrical installation when said fuse 8 is installed in the corresponding housing.

Examples of connectors 10 according to aspects of the invention are described in more detail in the following.

In the example given by way of illustration, the electrical installation comprises three connection bars 12a, 12b and 12c, each associated with an electrical phase.

For example, the connection bars 12a, 12b and 12c serve to distribute an electrical supply in the electrical installation and are supplied by an electrical source.

According to embodiments, for each pair of connectors 10, one of the connectors 10 (upstream connector) is electrically connected to a corresponding connecting bar 12a, 12b and 12c, for example by means of one or more electrically parts. conductors mounted in the housing 4.

For example, the connection bars 12a, 12b and 12c are arranged parallel and superimposed vertically at a distance from each other within an electrical panel. The device 2 is mounted vertically on the electrical panel by being connected to the connection bars 12a, 12b and 12c on a rear face of the box 4.

Conductors 14, such as cables, are used to connect the device 2 to an electrical load. For example, the conductors 14 are connected to a downstream connection zone 16 of the device 2 here formed on a lower part of the housing 4.

According to embodiments, the other connector 10 (downstream connector) of each pair is electrically connected to one of the conductors 14 by a contact bar 18a, 18b, 18c installed inside the device 2 and which connects said connector 10 to a corresponding conductor 14 via the connection area 16.

For example, each of the contact bars 18a, 18b, 18c extends into the housing 4 inside a side compartment along one or more housings 6. The contact bars 18a, 18b, 18c are preferably made of metallic material, for example copper or aluminum. Thus, each electrical connector 10 is electrically connected to an upstream or downstream electrical connection element of the disconnector 2.

In the example illustrated, for each housing 6a, 6b, 6c, the connectors 10 of each pair are arranged vertically one above the other in each housing. When the fuse 8 is in the housing 6a, 6b, 6c, the upstream and downstream terminals 20 of the fuse 8 are respectively connected to the upstream and downstream connectors 10 of this housing, as illustrated for the housing 6a in FIG. 1.

Figures 2 and 3 show embodiments of a connector 10 according to aspects of the invention.

The connector 10 has a base portion 22 and a plurality of first contact fingers 24 and second contact fingers 24 'arranged in succession along the base portion 22.

More precisely, the contact fingers 24 and 24 ’are arranged alternately on either side of a median geometric plane of the base portion 22.

For example, the first contact fingers 24 are disposed on one side of said midplane and the second contact fingers 24 'are disposed on the opposite side of said midplane.

It will be understood that, for example, the contact fingers 24 and 24 ’have a comb-shaped arrangement, the fingers of which would have been separated on either side of the median plane of the comb following a predefined pattern.

The contact fingers 24 and 24 'are here arranged in regular alternation, for example by arranging, contiguously two by two, a first contact finger 24, then a second contact finger 24, then another first contact finger 24 , And so on.

Other configurations can nevertheless be implemented in variants not illustrated here. For example, spaces can be provided between contact fingers 24 or 24 ’immediately adjacent. The periodicity of the pattern with which the contact fingers 24 and 24 ’are arranged can also be chosen differently.

In the example illustrated, the base portion 22 has the shape of a flat plate. The median plane therefore corresponds to the main plane of this plate, which here extends vertically.

The contact fingers 24 and 24 'are directly connected to the base portion 22 and extend essentially vertically and parallel from this base portion 22. For example, the contact fingers 24 and 24' form a single piece. holding with the base portion 22. The contact fingers 24 and 24 'delimit a longitudinal reception zone 26 configured to receive the terminal 20 of a fuse 8. In FIG. 2, the axis X20 illustrates the position of a terminal 20 of a fuse 8 when this fuse 8 is received in the corresponding housing 6.

When a terminal 8 is received in the reception area 26, the fingers 24 and 24 ’are in direct contact with the terminal 20 so as to establish electrical contact between the terminal 20 and the connector 10.

To this end, each contact finger 24 and 24 ’has a straight portion configured to come into direct contact with the terminal 20.

For example, the straight portion is parallel to the midplane. In the example shown, the right portion extends vertically.

In addition, the spacing of the fingers 24 and 24 ’from the median plane is chosen according to the width of the terminals 20 of the fuse 8.

According to embodiments, the contact fingers 24 and 24 ’have identical dimensions.

Preferably, each contact finger 24 and 24 'comprises a lower part 28 of inclined or curved shape which moves away from the base portion 22 by being directly connected to the base portion 22. The lower part 28 is immediately extended by the right portion of the contact finger.

Advantageously, each contact finger 24 and 24 ’comprises an upper part 30 flared outwards from the central reception area.

This arrangement allows the terminal 20 to be guided inside the reception area 26 when inserting the fuse 8.

Advantageously, the contact fingers 24 and 24 'each comprise a groove 32 formed on an outer face of the straight part, that is to say the face of the straight part which faces away from the reception area. 26. The groove 32 is adapted to receive an elastic return member, as described below.

The connector 10 is made of an electrically conductive material, for example a metal such as copper or aluminum, or a metal alloy, or any other suitable material or combination of materials.

According to examples, the connector 10 can be made from a plate-shaped base piece in which the fingers 24 and 24 'are formed by cutting and deformation. Alternatively, connector 10 can be formed by molding. For each connector 10, the fingers 24 and 24 'are connected to an upstream or downstream electrical connection element of the disconnector 2 via the base portion 22 and its extension.

Such a connector 10 can be used for all or part of the conductors 10 of the device 2. Preferably, the connectors 10 of the device 2 are identical.

According to examples illustrated in FIG. 2, the base portion 22 can be extended by a twisted portion 34 extending in the same direction towards a lower portion 35 which is itself connected to an end portion 36 here bent relative to the portion. lower 35. Alternatively, the twisted portion 34 may be omitted.

The terminal portion 36 is here configured to be electrically connected to an electrical connection element of the device 2, for example to one of the contact bars 18a, 18b, 18c or to one of the connection pieces connected to the distribution bars 12a, 12b, 12c.

According to embodiments, the connector 10 is a removable part mounted in the device 2. In this case, the end portion 36 may include a connection area 38 making it possible to fix the connector 10 to a corresponding electrical connection element. For example, the connection area 38 has an orifice suitable for receiving a fixing member such as a screw or a bolt.

According to other embodiments, the connector 38 is permanently linked with an electrical connection element of the device 2, such as one of the contact bars 18a, 18b, 18c, for example by being integrated at the end one of the contact bars 18a, 18b, 18c.

Thanks to the invention, the electrical connector 10 makes it possible to obtain good contact with the terminal 20 when the fuse 8 is connected, while being simple to manufacture. This reduces the risk that the fuse 8 is incorrectly connected or incorrectly mounted in the device 2.

According to embodiments, as illustrated in FIG. 3, the connector 10 comprises an elastic return element 40, such as a spring, associated with the contact fingers 24 and 24 'and configured to exert a return force laterally on the legs. straight portions of the contact fingers 24 and 24 '.

This keeps the straight portions of the contact fingers 24 and 24 "pressed in contact against the terminal 20, in order to obtain good electrical contact between the connector 10 and the terminal 20.

Preferably, the return element 40 is arranged so as not to hinder the entry and exit of the terminal 20 in the reception area 26. For example, the return element 40 comprises an elastic piece in the form of a wire and which surrounds the contact fingers 24 and 24 'from the outside, being inserted into the corresponding grooves 32 of the contact fingers 24 and 24'. The wire here has a circular section. According to examples, the return element 40 is made of metallic material or of elastomeric material.

For example, the return element 40 comprises a first essentially rectilinear portion in contact with the contact fingers 24 and received in the corresponding grooves 32, as well as a second essentially rectilinear portion in contact with the contact fingers 24 'and received. in the grooves 32 of these contact fingers 24 '.

The first portion and the second portion here extend essentially parallel to the X20 axis.

A curved portion 42 in the shape of a U and extending vertically interconnects the ends of the first portion and the second portion.

The first portion and the second portion may not be completely rectilinear and may have one or more tightened areas 44 at the space between two fingers 24 and 24 '.

According to alternative embodiments not shown, the biasing element 40 may have a different shape, or even be omitted. In the latter case, the grooves 32 can be omitted.

The embodiments and the variants envisaged above can be combined with one another to give rise to new embodiments.

Claims

1. Fuse-type electrical switching device (2), comprising: a housing (4) comprising at least one housing (6) for receiving a fuse (8); and at least one electrical connector (10) associated with said housing (6) for connecting an end terminal (20) of a fuse (8) when this fuse is inserted in the receiving housing; characterized in that the electrical connector (10) has a base portion (22) in the form of a flat plate and a plurality of first contact fingers (24) and second contact fingers (24 ') which form a piece of integrally with the base portion (22), the first contact fingers (24) and the second contact fingers (24 ') being arranged in succession along the base portion, alternately on either side a median geometric plane of the flat plate of the base portion (22), so as to delimit a longitudinal reception zone to accommodate the terminal (20).

2. Switching device (2) according to claim 1, wherein the contact fingers (24, 24 ’) have identical dimensions.

3. Switching device (2) according to any one of the preceding claims, wherein each contact finger (24, 24 ’) has a straight portion configured to come into direct contact with the terminal (20) of the fuse.

4. Switching device (2) according to any one of the preceding claims, wherein the electrical connector (10) is made of a metallic material.

5. Switching device (2) according to any one of the preceding claims, wherein at least part of the first contact fingers (24) and of the second contact fingers (24 ') has an upper part (30) flared towards outside the central reception area.

Switching apparatus (2) according to any one of the preceding claims, wherein the first contact fingers (24) and the second contact fingers (24 ') are connected to the base portion (22) by a part. lower (28) curved which moves away from the base portion (22).

7. Switching device (2) according to any one of the preceding claims, wherein the electrical connector (10) is electrically connected to an electrical connection element of the disconnector (2) via the base portion (22). ).

The switching device (2) according to any one of the preceding claims, wherein the connector (10) comprises an elastic return element (40) associated with the first contact fingers (24) and the second contact fingers (24). ').

9. Switching device (2) according to claim 7, wherein the first contact fingers (24) and the second contact fingers (24 ') comprise a groove (32) in which the elastic return member is received ( 40).

10. Switching device (2) according to any one of the preceding claims, wherein each receiving housing (6) comprises at least two such electrical connectors (10).