EP3555963A1

EP3555963A1 - Electrical connection element equipped with a contact element

Info

Publication number: EP3555963A1
Application number: EP17822424.2A
Authority: EP
Inventors: Martin Aumaitre
Original assignee: Legrand SNC; Legrand France SA
Current assignee: Legrand SNC; Legrand France SA
Priority date: 2016-12-15
Filing date: 2017-12-14
Publication date: 2019-10-23
Anticipated expiration: 2037-12-14
Also published as: ES2902205T3; CN110088982B; FR3060873B1; WO2018109402A1; RU2747849C2; CN110088982A; BR112019010810A2; RU2019116288A; RU2019116288A3; FR3060873A1; EP3555963B1

Abstract

The invention concerns an electrical connection element (1) comprising a conductive metal body (100) made from a first material and housing a spring leaf (200), the spring leaf being capable of pressing, against an inner face of a wall (103) of the body, the stripped core (4) of a conductive wire (2) inserted in said connection element. According to the invention, this inner face of the wall (103) of the body is equipped with a contact element (115) made from a second material, different from the first material, against which the spring leaf (200) is capable of pressing said stripped core of the conductive wire when it is inserted in the connection element, said second material having a contact resistance with the stripped core of the electrical wire that is less than the contact resistance between the first material and this stripped core of the electrical wire.

Description

ELECTRICAL CONNECTING ELEMENT HAVING A CONTACT ELEMENT

TECHNICAL FIELD TO WHICH THE INVENTION RELATES The present invention relates to an electrical connection element comprising a metallic conductive body made of a first material and housing a spring blade, said spring blade being adapted to press against an inner face of a wall of the body. the stripped core of a conductive wire inserted into said connection element.

It also relates to a method used to manufacture such an electrical connection element.

BACKGROUND

Such connection elements are known as described in the introduction, for example for electrical outlets.

The role of such a connection element is to carry the current between the electrical son of the electrical network and the electrical plug belonging to electrical equipment which is plugged into this connection element. The connection element comprises for this purpose a portion adapted to receive an electrical wire from the wall and a receiving cell adapted to receive the pin of the electrical plug to put in electrical contact.

Such an electrical connection element must comply with certain standards.

For example, the international standards require that the increase in temperature of an electrical outlet due to its heating in operation remains lower than a set heating threshold value as a function of the nominal intensity of the electrical outlet.

A solution to reduce heating of the connection element is to make the body of the connection element in a material having as low a resistance as possible, this body being completely covered with a coating limiting the contact resistance with the contact element. bare core of the electric wire. Indeed, heating of the connection element increases with the electrical resistance introduced by it into the electrical circuit.

The electrical resistance of the connection element is related to various parameters, in particular to the volume resistance of the material (related to its conductivity) and to the contact resistance between the stripped core of the electrical wire and the connection element. The body is usually made of raw brass. It is also known to make it entirely in brass coated with materials such as tin, silver or gold. This makes it possible to have a contact resistance with the stripped core of an electrical wire less than the contact resistance between the raw brass and the stripped core of the electrical wire. However, the cost of such coated brass is high.

An example of a connection element is for example described in document EP1353407.

OBJECT OF THE INVENTION

In this context, the present invention proposes a connection element in which heating during the electrical connection of an electric wire is reduced while limiting costs.

More particularly, it is proposed according to the invention an electrical connection element as described in the introduction, wherein the inner face of the wall of the body is provided with a contact element made of a second material different from the first material, against which said spring blade is adapted to press said stripped core of the conductive wire when it is inserted into the connection element, said second material having a contact resistance with the stripped core of the electrical wire less than the contact resistance between the first material and this bare core of the electric wire.

Thanks to the connection element according to the invention, it is possible to limit heating of the body of this connection element during the passage of the electric current by reducing the contact resistance between the stripped core of the electrical wire and the body, while by limiting the manufacturing costs of the connection element. This is achieved by means of a contact element made of a material having a contact resistance with the stripped core of the electrical wire less than that of the material in which the remainder of the connection element is made and disposed within the connection element.

Other non-limiting and advantageous features of the connection element according to the invention are the following:

said second material contains tin, silver or gold;

said first material contains copper;

- at least two contact elements made in the second material and said leaf spring is adapted to press the stripped core of the electric wire against at least one of the two contact elements;

at least two contact elements made in the second material are provided and said spring blade is adapted to press the stripped core of the electric wire against the two contact elements simultaneously;

each contact element extends projecting towards the inside of the body, with respect to the internal face of said wall;

each contact element belongs to a rivet fixed through said wall;

each contact element belongs to a patch placed on said inner face of the wall;

said body comprises at least two insertion corridors adapted to guide the insertion of the stripped core of the electrical wire into the connection element, each of the insertion passages being delimited at least partially by said internal face of the wall; of the body, and at least one contact element being disposed in each insertion channel.

The invention also relates to electrical equipment comprising a connection element as described above, for the electrical connection of an electric wire.

In particular, this electrical equipment constitutes a socket for the electrical connection of said electrical wire and a connection pin belonging to another electrical equipment.

The invention finally relates to a method of manufacturing an electrical connection element as described above, comprising a metal conductive body made of a first material and housing a spring blade, said spring blade being adapted to press against an inner face of a wall of the body denuded core of a conductive wire inserted in said electrical connection element, this inner face of the wall of the body being provided with a contact element made of a second material having a contact resistance with the denuded core of the electrical wire less than the contact resistance between the first material and the stripped core of the electrical wire, according to which said body is made in the first material, and then the element of the body is fixed on the inner face of the body contact made in the second material. According to this method, an orifice is drilled in said wall of the body and a rivet made in the second material is fixed thereto.

Alternatively, is welded to the inner face of said wall a pellet made in the second material.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT

The following description with reference to the accompanying drawings, given as non-limiting examples, will make it clear what the invention consists of and how it can be achieved.

In the accompanying drawings:

FIG. 1 is a schematic rear perspective view of a first embodiment of the electrical connection element according to the invention,

FIG. 2 is a schematic rear perspective view of the body of the electrical connection element of FIG. 1;

FIG. 3 is a schematic rear perspective view of the leaf spring of the electrical connection element of FIG. 1;

FIG. 4 is a rear view of the connection element of FIG. 1,

FIG. 5 is a diagrammatic front perspective view of the electrical connection element of FIG. 1,

FIG. 6 is a diagrammatic front perspective view of the body of the electrical connection element of FIG. 5;

FIG. 7 is a diagrammatic front perspective view of the leaf spring of the electrical connection element of FIG. 5,

FIG. 8 is a schematic view from above of the electrical connection element of FIG. 1,

FIG. 9 is a schematic view from above of the body of the electrical connection element of FIG. 8,

FIG. 10 is a schematic view from above of the leaf spring of the electrical connection element of FIG. 8,

FIG. 11 is a schematic side view of the electrical connection element of FIG. 1,

FIG. 12 is a diagrammatic profile view of the leaf spring of the connection element of FIG.

FIG. 13 is an exploded schematic view in front perspective view of the electrical connection element of FIG. 5; FIG. 14 is an exploded schematic rear perspective view of the electrical connection element of FIG. 1;

FIG. 15 is a diagrammatic sectional view along the plane P1 of FIG. 8,

FIG. 16 is a diagrammatic sectional view, similar to that of FIG. 15, with the stripped core of an electrical wire inserted in the connection element,

FIG. 17 is a schematic rear perspective view of a second embodiment of the electrical connection element according to the invention,

- Figure 18 is a schematic sectional view similar to that of Figure 16 for the second embodiment.

In the two embodiments shown, the identical or corresponding elements will be referenced by the same signs.

In Figures 1 to 16, on the one hand, and 17 to 18, on the other hand, there is shown a two embodiments of the connection element 1 according to the invention.

The connection element 1 according to the invention is intended to be integrated into an electrical equipment, for example to a power socket.

The electrical equipment according to the invention comprises at least one connection element for the electrical connection of an electric wire.

It authorizes the transport of the electric current between the electrical wires of this apparatus, for example the electrical wires of the electrical network connected to the electrical socket, and a connection pin plugged into this electrical equipment, for example belonging to an electrical plug. another electrical equipment.

This connecting element 1 comprises for this purpose a body

100 conductor comprising a housing 1 10 adapted to accommodate at least one stripped core 4 of an electrical wire 2 (Figure 16 and 18) and a cell 120 adapted to receive the connection pin of the electrical plug (not shown) to implement electrical contact the electrical wire with the connection pin. The connection element 1 further comprises a spring blade 200 adapted on the one hand to tighten the electric wire 2 introduced into the housing 1 10 against a base wall 103 of this housing 1 10, and secondly, to tighten the connection pin introduced into the connection socket 120 (FIGS. 1, 5, 8, 11, 13, 14, 15, 16, 17 and 18).

The electrical wire 2 more precisely comprises a stripped core 4 wrapped with an insulating sheath 3 (FIGS. 16 and 18).

More precisely, here the spring blade 200 is adapted to press the bare core 4 stripped of the conductor wire 2 inserted in the housing 1 against the base wall 103 (FIGS. 16 and 18) of this housing 1 10 and is adapted to at least one wall of the connection cell 120 is pressed against the connection pin when it is inserted into said connection cell 120.

The connection element 1 extends generally along a longitudinal axis X1 orthogonal to an insertion direction I of the connection pin in the cell 120. The insertion direction I corresponds to the longitudinal axis of the cell 120 receiving (Figures 1, 5, 8, 13, 14 and 17).

The body 100 of the connection element 1 is more particularly shown in FIGS. 1, 2, 4, 5, 6, 8, 9, 11, 13, 14 and 17.

The body 100 is made of a first material having a first satisfactory electrical conductivity for conducting the electric current between the connection pin and the electric wire 2.

This is for example a conductive metal, for example copper or an alloy containing copper.

The body 100 is here formed of a folded metal strip.

This body 100 here comprises two lateral wings 101, 102 which extend from the base wall 103, generally along the longitudinal axis X1.

The base wall 103 is substantially planar and extends perpendicularly to the longitudinal axis X1 of the connection element 1 (FIGS. 8, 9 and 17).

Each lateral wing 101, 102 forms, successively from the base wall 103, a main side wall 11, January 12 of the housing 1 10, an intermediate portion 121, 122 curved towards the inside of the connection element 1 and a cambered wall 123, 124 towards the outside of the connection element, which partially delimits the cell 120 (Figures 1, 2, 5, 6, 8, 9, 13, 14 and 17). The side walls 1 1 1, 1 12 of the housing 1 10, defined by the two lateral wings 101, 102, are flat and extend at right angles from the base wall 103.

This base wall 103 then forms a third side wall of the housing 1 10 (Figures 1, 2, 4, 5, 8, 9 and 17).

The housing 1 10 of the connecting element 1 then has a generally parallelepiped shape delimited by the two main side walls 11, 1, 12, the base wall 103 and said intermediate portions 121, 122 of the lateral wings 101, 102 ( Figures 1, 2, 5, 6, 8, 9, 13, 14 and 17).

This housing 1 10 is thus practically closed on four sides by said side walls 11 1, 12, 103 and said intermediate portions 121, 122 of the lateral wings 101, 102.

It is completely open on two opposite sides.

The housing 1 10 thus constitutes an insertion space of the electrical wire in the connection element 100, which extends here in a direction E1 parallel to the insertion direction I of the connection pin in the cell (FIGS. 2, 6, 9 and 1 1).

The insertion direction E1 of the electrical wire is here orthogonal to the longitudinal axis X1 of the connection element 1.

The housing 1 10 is open along this direction E1.

In addition, the base wall 103 of the housing 1 10 has a flat 105, forming two walls 106 which rise from the inner face of the base wall 103, parallel to the side walls 1 1 1, 1 12 housing 10 (FIGS. 5, 6, 8, 9 and 17), towards the interior of the housing 1 10.

These walls 106 extend longitudinally along the insertion direction E1 of the electrical wire in the housing over a large part of the height of the housing 1 10 (FIGS. 1, 2, 5, 6, 8, 9, 13, 14 and 17).

Thus, each wall 106 delimits with the side wall 1 1 1, 1 12 of the adjacent housing 1 10, an insertion corridor 107, 108 (Figure 9) of the stripped core 4 of the electric wire 2, which guides the introduction the stripped core 4 of the electrical wire 2 in this housing 1 10.

Remarkably, the inner face of the base wall 103 of the body 100 is further provided with a contact element 1 15 (Figures 8, 9, 15, 16, 18) made of a second material having a contact resistance with the stripped core of the electrical wire less than the contact resistance between the first material and the stripped core of the electric wire, against which said spring blade 200 is adapted to press said stripped core 4 of the conductor wire 2 when it is inserted into the connection element 1.

This second material is different from the first material.

It is a contact element with small dimensions compared to the dimensions of the base wall.

This contact element 1 thus has a limited extent compared to that of the base wall 103.

However, it can present different forms. It may in particular be in the form of a contact bump or a pellet, but other forms are also possible, for example a band form.

In particular, the contact element 1 may have a circular shape with a diameter of between 1 and 2 millimeters, for example equal to 1.5 millimeters. It may also have any other suitable form, with for example an overall dimension of between 1 and 2 millimeters. The corresponding dimensions of the housing are here for example 8 millimeters wide and 11 millimeters high along the insertion direction E1 for the base wall 103, and 7 millimeters long along the longitudinal axis X1. The total length of the connection element along this longitudinal axis X1 is here 18 millimeters.

Each contact element 1 15 is fixed on the inner face of the base wall 103. In particular, each contact element 1 15 is fixed in or on the base wall 103.

It can also be provided that the base wall 103 has a plurality of contact elements 1 against which the spring blade 200 is adapted to simultaneously or nonplate the stripped core 4 of the electric wire 2.

Each contact element 1 15 is adapted to convey the electric current from the stripped core of the electrical wire in contact with it to the body 100.

The body 100 is adapted to convey the electric current from each contact element 1 15 to the connection pin plugged into the cell 120 receiving.

In the first embodiment shown in FIGS. 1 to 16, as shown more particularly in FIGS. 1, 2 and 4, the element of FIG. connection 1 here more specifically comprises two contact elements 1 15.

The contact elements 1 15 are arranged on the inner face of the base wall 103 so that the leaf spring 200 plates the stripped core 4 of the wire 2 inserted in the housing 1 10 against at least one of the elements contact 1 15.

In practice, here, each contact element 1 15 is disposed in one of the insertion corridors 107, 108 delimited between the walls 106 and the adjacent side walls 11, 1, 12 (FIGS. 8 and 9), in the vicinity from the entrance to housing 1 10.

The inlet of the housing 1 10 corresponds to the open face of the housing 1 10 located closest to the second end portion 220 of the leaf spring 200, which will be described in more detail later.

Alternatively, the contact element may be placed in the middle of the insertion path of the stripped core of the electrical wire, or at any location ensuring the electrical contact between the contact element and the stripped core of the electrical wire.

Here, a contact element 1 15 is provided in each of the two insertion paths 107, 108 of the housing 1 10, and the stripped core 4 of the electrical wire 2 is thus brought into contact with one of the two contact elements. 1 regardless of the insertion corridor 107, 108 into which it is introduced.

Alternatively, a plurality of contact elements may be provided in each housing insertion corridor.

Thus, in the second embodiment shown in the figures

17 and 18, there are provided two contact elements 1 15 in each insertion channel 107, 108 of the housing 1 10. These contact elements are here placed near the entrance and the exit of the housing 1 10. A the exception of the number of contact elements disposed on the internal face of each insertion corridor, the connection element according to the second embodiment of FIGS.

18 is entirely similar to that of the first embodiment.

The stripped core is then pressed against at least one of the two contact elements 1 15 of the insertion corridor 107, 108 in which it is inserted.

The contact between the contact element and the stripped core of the electrical wire is then ensured, regardless of the direction in which the stripped core is inserted into the insertion corridor. When the bare core of the electric wire is inserted parallel to the insertion direction E1 in the housing 1 10, the core stripped 4 of the electrical wire 2 is pressed simultaneously against the two contact elements 1 15, which contributes to reducing the contact resistance of the assembly.

It may happen that the electric wire is biased in a direction orthogonal to the insertion direction E1. The stripped core 4 of the electric wire can then be placed in the housing in a direction inclined with respect to the insertion direction E1.

In this situation, the presence of two contact elements 1 15 ensures that the stripped core 4 of the electrical wire 2 is in contact with at least one of the two contact elements 1 15. For example, if the wire electrical outlet is pulled from the side of the receiving cell (to the left in Figure 18), the stripped core 4 of the electric wire remains in contact with the contact element 1 15 disposed near the outlet of the housing 1 10 If the electric wire is pulled from the opposite side to the receiving cavity (to the right in FIG. 18), the stripped core 4 of the electric wire remains in contact with the contact element 1 15 disposed near the entrance to housing 1 10.

The contact between the contact element 1 15 and the stripped core of the electric wire is exerted here on a reduced area of the stripped core because of the small dimensions of the contact element or elements.

Said second material preferably contains tin, silver, gold or another precious metal such as palladium, rhodium or platinum.

In practice, these are, for example, copper or tin-plated brass, that is to say copper or tin-covered raw brass, a copper / tin alloy, tin, an alloy of metals comprising gold, silver or other precious metal such as palladium, rhodium or platinum or a metal such as brass coated with gold, silver or other precious metal such as palladium, rhodium or platinum.

The copper or brass may be coated with tin, gold, silver for example by electrolytic deposition, compaction, co-rolling or co-rolling with solder.

In general, the contact resistance existing between the second material and the bare core of the electric wire can be measured by any method known to those skilled in the art.

This is to measure the potential drop between the stripped core of the electrical wire 2 and the contact element 1 15 made in this second material, so on both sides of the contact interface, for the application of a given setpoint current. The contact resistance is deduced from this measurement.

The contact resistance can in particular be measured for the application of a low current, for example of the order of 10 to 100 milliamps, and / or for the application of the nominal current of the connection element 1, for example between 16 and 20 amperes.

The contact resistance between the second material and the stripped core of the electrical wire and the contact resistance between the first material and the stripped core of the electric wire measured for the same value of the intensity of the electric current are preferably compared.

The contact resistance can be measured under operating conditions of the connection element, that is to say in the chemical and mechanical environment of use and after a certain aging of the connection element. The contact resistance between the second material and the stripped core of the electrical wire and the contact resistance between the first material and the stripped core of the electrical wire measured for similar operating conditions will preferably be compared.

The contact resistance between the first material and the stripped core of the electrical wire is for example measured in a contact element similar to that of the invention, but having no contact element.

This contact resistance depends in particular on the characteristics of hardness, sensitivity to mechanical stresses and resistance to chemical attack of the material.

For example, with a second relatively soft material such as tin, the oxides that can form on the surface of the contact element are cracked when the stripped core of the electrical wire is pressed against this contact element, which reduces the contact resistance between the stripped core of the electrical wire and the contact element.

More precisely, here, each contact element 1 15 belongs to a rivet 1 17 (see in particular FIGS. 13 to 16).

The base wall 103 is thus equipped with two rivets 1 17 made in said second conductive material. These are rivets 1 17 made of tin.

Each rivet January 17 is riveted to the base wall 103, through an orifice 1 16 of this base wall 103 (Figure 14). Each rivet 1 17 has two ends 1 15, 1 18 which protrude from said base wall 103 (Figures 15, 16 and 18).

The inner end 1 15 of the rivet 1 17 then protrudes from the wall 103, towards the interior of the housing 1 10 (Figures 15, 16 and 18), and constitutes the contact element 1 15.

This contact element 1 then has for example a projecting thickness of the base wall 103 of between 0.3 and 0.4 millimeters.

According to an alternative embodiment not shown here, the contact element belongs to a patch placed on said inner face of the base wall of the housing.

This pellet is for example welded to said inner face of the base wall at the point where protrudes the inner end 1 15 of the rivet 1 17 in the embodiment detailed here.

The two side walls 1 1 1, 1 12 of the housing 1 10 are extended by the two intermediate portions 121, 122 curved which are close to one another, then by the two arched walls 123, 124 which delimit between them. cell 120.

This cell 120 generally has the shape of a cylindrical sleeve whose longitudinal axis extends in the direction of insertion I (Figures 1, 2, 5, 6 and 17).

The intermediate portions 121, 122 of the lateral wings 101, 102 connect the edges of the main side walls 11, 11 to the cambered walls 123, 124 of the cell 120.

Each intermediate portion 121, 122 comprises successively, from the side wall January 1, 1 12 main corresponding, a fold 104 inwardly of the connecting member 1, a curved portion 121A, 122A outwardly , and a planar portion 121B, 122B. The two planar portions 121B, 122B extend parallel to each other, close to each other (Figures 2, 5 and 8).

The fold 104 here has a radius of curvature less than that of the arched portion 121 A, 122A (Figures 5, 6 and 9).

Each of the planar portions 121B, 122B is extended by one of the cambered walls 123, 124 partially forming the cell 120. Each cambered wall 123, 124 is arched towards the inside of the connecting member 1 and has the along the insertion direction I, an end 123A, 124A which is flared to facilitate the insertion of the connecting pin into the cell 120 (Figures 1, 2, 6, 8, 9 and 17).

Note that here, the inlet of the housing 1 10 and the flared entry of the cell 120 are disposed on either side of the connection element 1, imposing a direction of insertion of the electrical wire and the opposite connection pin.

The leaf spring 200 has the shape shown in Figures 3, 7, 10 and 12 to 18. The leaf spring 200 of the first and second embodiments are identical.

The spring blade 200 of the connecting element 1 according to the invention is formed in one piece by a metal ribbon whose first end portion 210 comprises a longitudinal slot 210A separating two branches 21 1, 212 adapted to tighten the arched walls 123, 124 of the cell 120 against the connecting pin (not shown) and a second end portion 220 of which is adapted to clamp the stripped core of the conductive wire inserted into the housing 1 against the wall of base 103 and the contact element 1 15.

The first end portion 210 has a free end 201 and the second end portion 220 has a free end 202.

The spring blade 200 has, flat, a substantially rectangular contour, slightly tapered at its first free end 201, which extends along a longitudinal direction.

It comprises two bent portions 233, 234 around a first transverse axis T1 and a second transverse axis T2 parallel to T1. These two transverse axes T1, T2 are perpendicular to the longitudinal direction of the metal strip.

Viewed in profile, the leaf spring 200 thus has a shape generally S (Figure 12), with the first and second end portions 210, 220 which respectively extend from one of said bent portions 234, 233 to one of the free ends 201, 202 of the leaf spring 200 and a central portion 230 located between the two bent portions 233, 234.

These three parts 210, 220, 230 of the leaf spring 200 are flat.

The longitudinal slot 210A here extends in the plane of the spring blade 200, along the first end portion 210, of one of the bent portions 234 and partially along the central portion 230 of the blade spring 200 (Figures 3 and 10). It separates the first end portion 210 of the leaf spring 200 into two front legs 21 1, 212 (Figure 3 and 10).

Said two front branches 21 1, 212 of the first end portion 210 extend in a mean plane of the spring blade 200 and are adapted to move elastically apart from each other parallel to this mean plane when the introduction of the connection pin into the connection element 1.

Furthermore, here, the second end portion 220 of the leaf spring 200 is also separated into two rear branches 221, 222 by another longitudinal slot 240 (Figure 10).

The free end of each of the two rear branches 221, 222 further comprises a notch adapted to match the contour of the stripped core 4 of the electric wire 2 introduced into the housing 1 10 of the body 100 of the connection element 1 ( Figures 8 and 10).

In practice, the spring blade 200 is housed in the body 100 so that the second end portion 220 and the third central portion 230 of the leaf spring 200 are housed in the housing 1 10 of the body 100 (FIGS. , 15, 16 and 18).

As shown in Figures 1, 5, 8, 15, 16 and 18, the central portion 230 of the leaf spring 200 is applied against a portion of the inner face of each arched portion 121 A, 122A of each intermediate portion 121, 122 of each lateral wing 101, 102 of the body 100 of the connection element 1. It then extends substantially parallel to the insertion direction I of the connection pin in the cell 120.

The leaf spring 200 has a width substantially equal, with a clearance, to the width of the insertion space formed internally by the housing 1 10 of the body 100, with the exception of a central zone of the leaf spring 200 which has a greater width because two lugs 231, 232 extend locally from the edge of the leaf spring 200 (Figure 3).

The leaf spring 200 has in fact holding means in the housing 1 10, which cooperate to hold with complementary means of the body 100 of the connecting element 1.

More precisely, here the central portion 230 of the spring blade 200 comprises the two lugs 231, 232 which extend in the plane of this central portion 230 of the spring blade 200, towards the outside of the leaf spring (FIG. 7 and 10).

Each of these ears 231, 232 is received in a window 109 of the body 100 of the connection element 1, located here at the fold 104 connecting the arched portion 121 A, 122A of the intermediate portion 121, 122 of each side wing 101, 102 to the corresponding side wall 1 1 1, 1 12 of the housing 1 10 (Figures 1, 5 and 1 1).

The spring blade 200 is thus snap-fitted in the body 100 of the connection element 1.

The shape of the lugs 231, 232 makes it possible to hold the spring blade 200 in the housing 1 10 during the insertion of the stripped core 4 of the electric wire 2.

The second end portion 220 of the spring blade 200 extends across the housing 1 10, and the free end 202 of the second end portion 220 of the leaf spring 200 is in abutment against the inner face of the base wall 103 of the housing 1 10 (Figure 7) when no conductive wire is inserted into the housing 1 10. Here, in addition, the free end 202 of the second end portion 220 of the blade spring 200 rests against the contact element 1 15 at rest.

The spring blade 200 may be slightly preloaded so that this second end portion 220 of the leaf spring 200 permanently exerts a pressure against the inner face of the base wall 103 of the housing 1 10 and / or on the spring element. contact 1 15.

More precisely, as shown in FIG. 8, the free end of each of the two rear branches 221, 222 of the second end portion 220 of the spring blade 200 is shaped so as to be housed in one of the two corridors insertion 107, 108 of the electrical wire.

The free end of each rear branch 221, 222 thus extends across one of the insertion channels 107, 108, between one of the side walls 1 1 1, 1 12 of the housing 1 10 and the wall 106 adjacent, and is in abutment against the base wall 103 and / or the contact element 1 15 (Figure 15) when the stripped core 4 of the wire 2 is out of the housing 1 10 of the connection element 1.

Alternatively, the spring blade can be housed at rest in said housing. The free end of each rear branch is not necessarily in contact with the base wall and / or the contact element before the introduction of the stripped core of the electrical wire. The first end portion 210 of the leaf spring 200 emerges from the housing 1 10 and extends towards the cell 120 (Figures 1 1 and 17).

This first end portion 210 of the spring blade 200 extends here then substantially perpendicular to the insertion direction I of the connection pin in the cell.

More specifically, here, the first end portion 210 of the leaf spring 200 emerges near the end 123A, 124A flared of the cambered portion 123, 124 of the side wing 101, 102 (Figures 1 1 and 17) .

In addition, as shown in FIGS. 1, 5 and 8, a part of the body 100 of the connecting element 1 extends in the longitudinal slot 210A, between the front branches 21 1, 212 of the spring blade 200. here is a portion of the planar portion 121 B, 122B of the intermediate portion 121, 122 of each side wing 101, 102 of the body 100 of the connecting member 1.

Indeed, as shown in Figure 10, the height of each lateral flange 101, 102 of the body 100, measured in the direction of insertion I of the connecting pin, is lower at the arched portion 121 A, 122A of the intermediate portion 121, 122 of this lateral wing 101, 102 at the level of the flat portion 121 B, 122B of the intermediate portion 121, 122.

This allows the first end portion 210 of the spring blade 200 to emerge over the edges of the arched portions 121A, 122A of the intermediate portions 121, 122, such that the free ends of the front legs 21, 212 of the first end portion 210 of the spring blade 200 frame the ends of the flat portions 121 B, 122B of the intermediate portions 121, 122 of the lateral wings 101, 102 (Figures 1 and 5).

The spring blade 200 is thus adapted to cooperate with said wings of the body 100 so as to limit the spacing of the cambered portions 123, 124 of the lateral wings 101, 102 delimiting the cell 120.

Here, in the standby position, when no pin is inserted into the receiving cell 120, the free ends of the front legs 21 1, 212 of the first end portion 210 of the leaf spring 200 are in position. contact with the flat portions 121 B, 122B of the intermediate portions 121, 122 of the lateral wings 101, 102, without exerting pressure on them.

Alternatively, in the standby position, the free ends of the front legs of the first end portion of the leaf spring may be out of the contact with the ends of the planar portions of the intermediate portions of the lateral wings.

Alternatively also, in this waiting position, the free ends of the front legs of the first end portion of the spring blade can pinch the ends of the flat portions of the intermediate portions of the side wings.

The material of the spring blade has satisfactory rigidity characteristics to play its role of tightening the electrical wire and the connecting pin. It is not necessary that it be made of a conductive material, which limits the amount of conductive material used to manufacture the connection element according to the invention. The leaf spring is for example made of steel, especially stainless steel.

In practice, thanks to the connection element 1 according to the invention, heating of the connection element 1 during the passage of the electric current of the electrical wire to the connection element is limited.

When inserting the stripped core 4 of the electrical wire 2 into the housing 1 10, the second end portion 220 of the spring blade 200 is adapted to flex slightly around the first transverse axis T1 to allow the introduction of this denuded soul in the corresponding housing 1 10.

Thus, when the stripped core 4 of an electrical wire 2 is introduced into the housing 1 10, along one of the insertion corridors 107, 108, the second end portion 220 flexes towards the central portion 230 the leaf spring 200 so as to release a passage for the stripped core 4 of the electric wire in the corresponding insertion corridor (Figure 16). When the stripped core 4 of the electrical wire 2 extends in the insertion corridor, the second end 220 of the spring blade 200 tends to return towards its uninflected rest position, thereby plating the stripped core 4 of the electric wire. 2 against the inner face of the base wall 103 of the housing 1 10 and against the contact element 1 15.

Here, two electrical son can be introduced into each connection element 1, in the two insertion corridors 107, 108 of the housing 1 10 described above.

Here, each electrical wire is inserted in a direction perpendicular to the longitudinal axis X1 of the connection element 1 and parallel to the insertion direction I of the connection pin. Each rear branch 221, 222 is adapted to flex independently of the other rear branch, to allow the insertion of the stripped core 4 of the electric wire 2 into one of the insertion corridors 107, 108, independently of the insertion of an electric wire into the other insertion channel.

The free end 202 of the stressed rear branch 221, 222 then exerts a pressure on the stripped core of the electric wire, so as to press it against the contact element 1 15 and the base wall 103 of the housing 1 10.

Thus, the stripped core 4 of the electrical wire 2 is pressed against the contact element 1 made in the second material having a reduced contact resistance with respect to the first material which constitutes the rest of the body of the electrical connection element. 1.

The presence of this contact element 1 15 interposed between the stripped core 4 of the electrical wire 2 and the part of the body 100 made of the first material makes it possible to reduce the overall contact resistance existing between the stripped core 4 of the electrical wire 2. and the connection element 1 and thus to limit heating of the assembly during the passage of the current.

The experimental results obtained by the Applicant show that the overall strength of the connection element according to the invention provided with tin rivets is similar to that of a connection element made entirely of tinned brass, without contact element.

In addition, the contact element 1 has a reduced size with respect to the connection element 1 and requires a small amount of second material to be manufactured. Its installation in the connection element is simple. The connection element 1 according to the invention is inexpensive.

The manufacturing cost of the connection element according to the invention is furthermore limited because the cutting waste of the material forming the body of the connection element (copper or brass for example) can be easily recycled and is therefore resold at a price close to the purchase price. On the contrary, if the body is made entirely of tinned brass for example, not only does this material cost more to buy, but it is also more difficult to recycle because the tin must be separated from the brass. The cutting waste is then resold at a price well below the purchase price. The connection element according to the invention is therefore economical to produce.

Moreover, in the described example of the connection element, the Electrical conduction and clamping functions of the connection pin and the electrical wire are decoupled.

The electrical conduction is provided solely by the body 100, while the spring blade 200 ensures the clamping of the connection pin in the connection cell 120 and the electrical wire in the housing 1 10.

In addition, the clamping of the connection pin and that of each electric wire is provided independently.

Indeed, during the insertion of the connection pin in the cell, it is engaged in the cell in the direction of insertion I, since the flared end of the cell 120 to the inside of the cell 120

In doing so, the connecting pin tends to separate from each other the cambered portions 123, 124 of the lateral wings 101, 102.

However, such spacing immediately causes the spacing of the flat portions 121 B, 122B of the intermediate portions 121, 122 of the lateral wings 10, 102.

The spacing of the flat portions 121 B, 122B of the intermediate portions 121, 122 of the lateral wings 101, 102 is when it is strongly limited by the action of the leaf spring 200 on these planar portions 121 B, 122B of the intermediate portions 121, 122 of the lateral wings 101, 102.

Indeed, this spacing tends to spread the front branches 21 1, 212 of the spring blade 200 in the plane of the spring blade 200. The leaf spring 200 is then biased in a transverse direction.

The leaf spring 200 has a low elasticity in this transverse direction, and only allows a small spacing of the flat portions 121 B, 122B of the intermediate portions 121, 122 of the lateral wings 101, 102.

Thus, during the insertion of the connection pin into the cell, the front branches 21 1, 212 of the spring blade move elastically, then tend to resume their initial positions.

The spring blade 200 thus cooperates with said wings of the body 100; 300 so as to oppose the spacing of the cambered portions 123, 124 4 of the lateral wings 101, 102 delimiting the cell 120.

In other words, the leaf spring 200; 400 cooperates with said wings of the body 100 to bring to one another the cambered portions 123, 124 of the lateral wings 101, 102 delimiting the cell 120. The front branches 21 1, 212 of the leaf spring 200 recall the plane portions 121 B, 122B of the intermediate portions 121, 122 of the lateral wings 101, 102 toward each other, and with them, the arched portions 123, 124 of the cell, so as to bring said arched portions 123, 124 closer to one another.

In doing so, the front branches 21 1, 212 of the leaf spring 200 ensure the clamping of the connection pin against the cambered portions 123, 124 of the cell.

The electrical connection of the electrical wire and the connection pin is thus secured effectively.

The connection element according to the invention as described above can be realized in different ways.

In practice, here, the body 100 is manufactured by folding a metal strip of the first conductive material, for example raw brass.

The windows 109 are pierced in the lateral wings 101, 102 as well as the flat 105 and the orifices 116 in the base wall 103. This is preferably done before the folding of the metal strip.

It is then possible to introduce into each orifice 1 16 a rivet 1 17 and to fix it, then finally to fold the strip. This is particularly the case during an automated assembly of the connection element 1.

As a variant, especially during a manual assembly, it is possible first of all to make a maximum of folds of the strip, that is to say those which will not interfere with the manual crimping, then to put the rivets 1 17 and finally to finalize the folding the strip.

The rivet 17 may be preformed or formed from a wire or a profile of the second material directly into the connecting member. For example, a pre-tinned wire having a square cross-section of 1 millimeter in length and 1.5 millimeters in length is used, crimped into the connection element.

Alternatively, instead of drilling the holes and installing the rivets is welded to the inner face of said base wall 103 two pellets made in the second material. This is preferably done before folding the metal strip.

There is described here a connection element having a particular non-limiting form. The connection element may have any other adapted form known to those skilled in the art.

It may especially be a connection element having a single insertion corridor delimited by the housing, in which a single electrical wire may be introduced. In this single corridor, one or more contact elements are provided according to the invention.

It may also be a connection element of different geometry, for example in which the insertion space of the electrical son or wires in the housing extends in a direction perpendicular to the direction of insertion of the spindle. in the cell. Similarly, the leaf spring may have a different shape.

It may also be a simpler connection element, comprising only a housing and a spring blade, such as an automatic terminal, without receiving cell of a connection pin. Finally, the number of connection element and their shape can obviously vary.

Claims

1. Electrical connection element (1) comprising a metal conductive body (100) made of a first material and housing a spring blade (200), said spring blade (200) being adapted to press against an inner face of a wall (103) of the body (100) the stripped core (4) of a conductive wire (2) inserted into said connection element (1), characterized in that this internal face of the wall (103) of the body (100) is provided with a contact element (1 15) made in a second material different from the first material, against which said spring blade (200) is adapted to press said stripped core (4) of the conductive wire (2) when it is inserted in the connection element (1), said second material having a contact resistance with the stripped core of the electrical wire less than the contact resistance between the first material and the stripped core of the electrical wire.

An electrical connection element (1) according to claim 1, wherein said second material contains tin, silver or gold.

3. Electrical connection element (1) according to one of claims 1 and 2, wherein said first material contains copper.

4. An electrical connection element (1) according to one of the preceding claims, wherein there is provided at least two contact elements made in the second material and said spring blade (200) is adapted to press the stripped core (4). ) of the electric wire (2) against at least one of the two contact elements.

5. Electrical connection element (1) according to one of claims 1 to 4, wherein each contact element (1 15) extends inwardly projecting from the body (100), relative to the inner face of said wall.

6. Electrical connection element (1) according to one of claims 1 to 5, wherein each contact element (1 15) belongs to a rivet (1 17) fixed through said wall (103).

7. Electrical connection element according to one of claims 1 to 5, wherein each contact element belongs to a patch on said inner face of the wall.

8. An electrical connection element (1) according to one of claims 1 to 7, wherein said body (100) comprises at least two insertion corridors (107, 108) adapted to guide the insertion of the stripped core (4) of the electrical wire (2) into the connection element (1), each of the insertion corridors (107, 108) being delimited at least partially by said internal face of the wall (103) of the body, and at least one contact element (1 15) being disposed in each insertion channel (107, 108).

9. Electrical apparatus comprising a connection element (1) according to one of the preceding claims, for the electrical connection of an electric wire.

10. Electrical apparatus comprising a connection element (1) according to the preceding claim, constituting a socket for the electrical connection of said electrical wire and a connection pin belonging to another electrical equipment.

1 1. A method of manufacturing an electrical connection element (1) according to one of claims 1 to 8, comprising a metal conductive body (100) made of a first material and housing a spring blade (200), said spring blade (200) ) being adapted to press against an inner face of a wall (103) of the body (100) the stripped core (4) of a conductive wire (2) inserted in said electrical connection element (1), this internal face the wall (103) of the body (100) being provided with a contact element (1 15) made of a second material having a contact resistance with the stripped core of the electrical wire less than the contact resistance between the first material and the stripped core of the electrical wire, according to which said body (100) is cut in the first material, and then the contact element (1) is fixed on the inner face of the wall (103) of this body (100). ) made in the second material.

12. The manufacturing method according to the preceding claim, wherein an orifice (1 16) is pierced in said wall (103) of the body (100) and a rivet (1 17) made in the second material is fixed thereto.

13. The manufacturing method according to claim 1 1, wherein is welded on an inner face of said wall a pellet made in the second material.