Magnetic connector and group of magnetic connectors

A magnetic connector for connecting an electrical unit to an electrical consumer unit includes at least one magnet, a conductive metal part secured to this magnet, a connecting cable fixed to the conductive metal part, and a cap made of plastic material overmoulded on the connecting cable, the conductive metal part and the magnet, except for a contact surface of the magnet intended to make contact with a metal part of the electrical consumer unit.

TECHNICAL FIELD

The present invention relates to a magnetic connector for connecting an electrical unit to an electrical consumer unit. The invention also relates to a group of connectors comprising such magnetic connectors.

BACKGROUND

For various uses, notably for measuring energy consumption, temperature measures, electrical testing or supplying electrical power to miscellaneous electrical units, it is sometimes necessary to connect a cable to a voltage source of an electrical consumer unit, for example a circuit breaker screw. Usually, it is necessary to unscrew a screw and to rescrew it after having fitted an electrical cable to obtain the current. This operation is impractical and unreliable, all the more so when the space available between the screws of the circuit breakers and the front cover of an electrical consumer unit is reduced.

SUMMARY

It is these drawbacks that the invention intends to remedy by proposing a magnetic connector allowing an electrical unit to be connected to an electrical consumer unit more easily and more reliably.

To this end, the invention relates to a magnetic connector for connecting an electrical unit to an electrical consumer unit. This magnetic connector is characterized in that it comprises at least one magnet, a conductive metal part secured to this magnet, a connecting cable fixed to the conductive metal part, and a cap made of plastic material overmoulded on the connecting cable, the conductive metal part and the magnet, except for a contact surface of the magnet intended to make contact with a metal part of the electrical consumer unit.

By virtue of the invention, the magnetic connector ensures both the mechanical securing and the electrical connection, simplifying the connection of electrical units.

According to advantageous but non-mandatory aspects of the invention, a magnetic connector can incorporate one or more of the following features, taken in any technically admissible combination:The connector comprises a single magnet of cylindrical form and having a circumferential groove in which the material of the cap made of plastic material is engaged.The connector comprises two magnets of reverse polarities.The two magnets are of semicylindrical form and separated from one another by a wall made of a single piece with the cap.The cap made of plastic material has a longitudinal part extending along a central axis and terminated by a flat surface parallel to the contact surface of said at least one magnet, and the cable is oriented transversely with respect to the longitudinal part and then encapsulated in a radial part of the cap which extends the flat surface.The longitudinal part comprises at least one peripheral gripping ridge provided in the extension of the radial part of the cap.The longitudinal part is of cylindrical form and has at least one longitudinal bulge so as to produce friction in a housing of the electrical consumer unit in which the connector is connected.The longitudinal part has an elliptical transverse profile of which the greatest dimension has a length, with respect to the smallest dimension, that is greater by 0.2 to 0.4 mm.The longitudinal dimension of the connector, taken between the contact surface of the magnet and the flat surface of the cap, is between 7 and 12 mm.

The invention also relates to a group of magnetic connectors, characterized in that it comprises at least two magnetic connectors as mentioned above, each of these magnetic connectors being intended to be connected to a metal part of the electrical consumer unit, and a link part to which each of these magnetic connectors is fixed with a predefined separation.

DETAILED DESCRIPTION

FIGS.1and2represent an electrical cabinet2, comprising a closing cover20and an electrical consumer unit22. The electrical consumer unit22comprises a circuit breaker24and a protective cover26forming a front panel of the electrical consumer unit22. The circuit breaker24is linked to several screws, of which at least one is represented inFIG.2with the reference28, which are screwed onto electrical terminals30, or cages, seen in cross section inFIG.2, and which fix and electrically connect to cables32by which the circuit breaker24is supplied with electrical current. The screw28is inserted into a housing34of a socket36of the circuit breaker24. The socket36is separated from an internal face of the protective cover26by a space E.

FIG.2represents a magnetic connector5for connecting an electrical unit (not represented), this magnetic connector5being connected to the electrical consumer unit22, and more specifically to the screw28.

As can be seen inFIG.3, the connector5comprises at least one magnet50, a conductive metal part52secured to this magnet50, a connecting cable54fixed to the conductive metal part52, and a cap made of plastic material56, overmoulded on the connecting cable54, the conductive metal part52and the magnet50, except for a contact surface500of the magnet50, that is intended to make contact with the screw28of the electrical consumer unit22.

The magnet50adheres to the screw28by virtue of the magnetic attraction between the screw28and the contact surface500, which is flat. The magnet50therefore ensures the mechanical anchoring of the connector5on the screw28.

According to a first embodiment represented inFIGS.3to8, the magnetic connector5comprises a single magnet50of cylindrical form centred around a central axis X5. The contact surface500is of circular form and at right angles to the central axis X5.

The magnet50has a circumferential groove50A in which the material of the cap made of plastic material56is engaged. This groove50A makes it possible to reinforce the mechanical anchoring of the magnet50in the plastic cap56.

The conductive metal part52has the form of a washer centred on the central axis X5. This part52is fixed to the magnet50by magnetic attraction. The conductive metal part52is preferably made of a paramagnetic metal material.

The connecting cable54has a stripped end540which is soldered onto the conductive metal part52. Thus, there is an electrical continuity between the magnet50, the conductive metal part52and the cable54.

The cable54is linked to an electrical apparatus which is not represented, for example a voltage or temperature or other such detector.

The cap made of plastic material56has a longitudinal part560extending along the central axis X5and terminated by a flat surface562parallel to the contact surface500of the magnet50. The magnet50and the conductive metal part52are housed in this longitudinal part560. The connecting cable54is oriented transversely with respect to the longitudinal part560and encapsulated in a radial part564of the cap56, which extends the flat surface562.

The longitudinal part560comprises at least one peripheral gripping ridge560A provided in the extension of the radial part564. This ridge560A forms a protuberance of the longitudinal part560and allows a user to manipulate the connector5, notably by passing his or her finger or fingernail under the ridge560A to grip the connector5, or to separate it from the screw28. In a variant that is not represented, the connector5can have more than one ridge560A, for example two parallel ridges.

The longitudinal part560is of cylindrical form centred on the central axis X5and has at least one longitudinal bulge560B so as to produce friction in the housing34.

In this example, the longitudinal part560has two longitudinal bulges560B diametrically opposite with respect to the central axis X5, formed by the fact that the longitudinal part560has an elliptical transverse profile, of which the greatest dimension L1has a length, with respect to the smallest dimension L2, that is greater by 0.2 to 0.4 mm. The greatest dimension L1here forms the greatest diameter of the ellipse formed by the base of the cylinder forming the longitudinal part560, whereas the smallest dimension L2corresponds to the smallest diameter. These longitudinal bulges560B make it possible to reinforce the mechanical anchoring of the connector5in its housing34by friction, which is added to the magnetic attraction of the magnet50. According to a variant which is not represented, the longitudinal bulges could also be formed by protuberances such as ridges.

The longitudinal dimension L5of the connector5, taken along the central axis X5between the contact surface500and the flat surface562, is preferably between 7 and 12 mm. This small bulk allows the magnetic connector5to be easily housed in an electrical consumer unit under the protective cover26in the space E. Also, the part of the connector5extending beyond the housing34, that is to say the radial part564and its extension on the longitudinal part560surrounded by the ridge560A, and the radial orientation of the cable54, mean that the connector5has a small protruding height, which allows it to be housed in the space E.

FIG.4shows the connecting of the connector5to the screw28. The terminal30is seen uncut and without cable32. A part of the magnet50which bears the contact surface500protrudes from the overmoulded cap56on the central axis X5. The magnet50and the screw28are subjected to a magnetic attraction force augmented by the friction force exerted by the bulges560B in the housing34, to give a mechanical holding force equivalent to a weight of between 500 g and 1 kg.

The electrical current is conducted between the terminal30and the screw28. The electrical resistance of the terminal30+screw28assembly is preferably between 0.1 and 0.3Ω. The electrical current is conducted between the head of the screw28and the magnet50, with a contact resistance preferably of between 0.1 and 0.3Ω.

FIGS.6to8represent a method for manufacturing the magnetic connector5. InFIG.6, the connecting cable54with its stripped part540is soldered onto the conductive metal part52. InFIG.7, the magnet50is fixed to the conductive metal part52by magnetic attraction. InFIG.8, the assembly formed by the stripped part540, the conductive metal part52and the magnet50is placed in an injection mould which is not represented, for example a low-pressure mould, into which the plastic material is injected to mould the plastic cap56and obtain the final connector5as it appears inFIG.4.

A second embodiment of the invention is represented inFIGS.9and10. In this embodiment, the elements that are common to the first embodiment bear the same references and operate in the same way.

In this embodiment, the connector5comprises two magnets7and9of reverse polarities. The two magnets7and9are preferably of semicylindrical form separated from one another by a wall566made of a single piece with the plastic cap56. This wall566makes it possible to ensure the magnetic and physical isolation of the two magnets7and9. The wall566is aligned with the central axis X5.

Each of the magnets7and9has a respective semi-circular contact surface70and90, and a respective peripheral groove72and92.

According to variant that is not represented, the conductive metal part52can have two positioning housings for the magnets7and9in order to ensure that they are not attracted by magnetic force prior to their overmoulding in the plastic cap56.

A third embodiment of the invention is represented inFIG.11. In this embodiment, several magnetic connectors5can be linked in parallel to several conductive parts28of the electrical consumer unit22. These magnetic connectors5are grouped together in the form of groups of magnetic connectors comprising at least two connectors.

FIG.11illustrates a set of three groups of connectors5A,5B, and5C. The first group of connectors5A comprises two magnetic connectors5and a link part4A which mechanically links these two magnetic connectors5to one another, for the mechanical hold, and to ensure an electrical safety distance D1between them. The magnetic connectors5are fixed to the link part4A by the clamping of the caps56of the magnetic connectors5into two clamps of the link part4A.

The second group of connectors5B comprises two magnetic connectors5and a link part4B which mechanically links these two magnetic connectors5to one another, while maintaining an electrical safety distance D2, greater than the distance D1, for the case where the separation that is necessary between the connectors5to correspond with the separation of the conductive parts28is greater.

The third group of connectors5C comprises four magnetic connectors5and a link part4C which comprises four clamps each receiving one of the four magnetic connectors5while maintaining a separation between these four magnetic connectors.

The link parts4A,4B,4C inFIG.11are illustrated by way of example, other link parts between the magnetic connectors5being able to be provided.