EP2533374A1

EP2533374A1 - Connector assembly with a magnetic fixation

Info

Publication number: EP2533374A1
Application number: EP11004567A
Authority: EP
Inventors: Ulrich Mense; Hasan Karaca
Original assignee: Novero GmbH
Current assignee: Novero GmbH
Priority date: 2011-06-06
Filing date: 2011-06-06
Publication date: 2012-12-12

Abstract

The invention relates to a connector assembly (1) for electrically connecting a first electrical or electronic item to a second electrical or electronic item, comprising a first connector (2) having a first magnetic assembly (3) with at least one magnetic element and having at least two contacts (4) of an electrically conductive material, electrically connected to one of the first and second electrical or electronic items and electrically insulated from each other, and a second connector (5) having a second magnetic assembly (6) with at least one magnetic element and having at least two contacts (7) of an electrically conductive material, electrically connected to the other of the first and second electrical or electronic items and electrically insulated to each other, wherein the contacts (4) of the first connector (2) are maintained in electrically conductive relationship with the contacts (7) of the second connector (5) by magnetic attraction between the first magnetic assembly (3) and second magnetic assembly (6). This connector assembly (1) is constructed so that the contacts (4) of one of the connectors (2) are designed as concentric tracks (4), the contacts (7) of the other of the connectors (5) are positioned such that in a coupled state of the connector assembly (1) each single contact (7) of the other connector (5) abuts on a different contact (4) of the one connector (2), the two connectors (2,5) can, in principle, be coupled in more than two angular positions relative to each other and to a central axis (8) common to the concentric tracks (4) with always the same pair of contacts (4,7) being in electrically conductive relationship in a coupled state of the connector assembly (1), and the first connector (2) has at least one guide (9) and/or the second connector (5) has at least one guide (10) which are arranged such that in a coupled state of the connector assembly (1) they prevent a displacement of the connectors (2,5) relative to each other which would result in a loss of the electrically conductive relationship of a contact (4) of the first connector (2) with the corresponding contact (7) of the second connector (5).

Description

The present invention relates to a connector assembly with the features according to the preamble of claim 1.
Connector assemblies of the kind in question serve to electrically connect a first electrical or electronic item, such as an electrical or electronic circuit, e.g. an electricity consumer like a laptop, to a second electrical or electronic item, such as a power supply or an associated cord or cable. The connection between the two items may be temporary or permanent.
A connector assembly is disclosed in US 7,311,526 B2 which forms the starting point of the present invention. The known connector assembly includes two connectors, preferably a plug and a receptacle. The plug and the receptacle each have a plurality of contacts of an electrically conductive material. The contacts of each of the connectors are electrically connected to an electrical or electronic item and electrically insulated from each other. The contacts of the plug mate the contacts of the receptacle. Furthermore, the plug and the receptacle each have a magnetic element. The contacts of the plug are maintained in an electrically conductive relationship with the contacts of the receptacle by magnetic attraction between both magnetic elements.
Magnetically coupling the plug and the receptacle enables a comfortable handling and avoids damage of the connector assembly and in particular the associated electric items, because the connectors are not required to have an interference fit with each other to maintain both electrical and mechanical connection. Instead, establishing and releasing an electrical and magnetic connection between the plug and the receptacle basically requires positioning the connectors on a face side against or away from each other. The magnetic connection allows the coupled connectors to break away from each other without damage when inadvertently torn apart from each other by a non-axial force.
The connectors of the known connector assembly each comprise two axes of symmetry such that the connectors couple together in only two orientations relative to each other. Furthermore, when coupling the plug and the receptacle, the contacts of the plug have to be aligned with the contacts of the receptacle. Such an alignment may require several iterations of repositioning of the connectors.
Therefore, the object of the present invention is to improve the known connector assembly with regard to the handling.
The object mentioned above is met by a connector assembly comprising the features of the preamble of claim 1 together with the features of the characterizing part of claim 1.
In contrast to the prior art, the contacts of one of the two connectors of the connector assembly according to the present invention are concentric tracks. These concentric tracks offer a large contact surface, while the concentric tracks can have a very small axial extension. This feature is especially advantageous for electronic devices for which the axial connector extension is subject to more severe restrictions than lateral extension of the connector.
Further, as the concentric tracks are at least substantially flat, the contacts of the other of the connectors are prevented from being damaged by being jammed in, for example, a recess or slot, at a wrong angle or by being fitted into imperfectly fitting cavities. In addition, a substantially flat design of the contacts of one of the connectors provides advantages in terms of electrical characteristics, such as issues related to Hertzian stresses around a contact point and issues related to contact asperities.
The concentric tracks combined with the coupling of the connectors by magnetic force enable a high durability of the connector assembly in terms of many coupling/decoupling cycles.
According to the invention the contacts of the other of the connectors are positioned such that in a coupled state of the connector assembly each single contact of the other connector abuts on a different contact of the one connector. Thus, each contact pair establishes a separate electrical path in a coupled state of the connector assembly. This arrangement is essential to avoid short-circuiting.
In sharp contrast to the prior art, the two connectors can, in principle, be coupled in more than two angular positions (orientations) relative to each other and to a central axis common to the concentric tracks. This feature simplifies the handling of the inventive connector assembly, especially the coupling process. Potentially, the connectors can be coupled in many different orientations. This feature allows an easy and rapid coupling of the connectors.
The combination of this feature with the feature of concentric tracks according to the present invention yields another important advantage over the prior art. Coupling the inventive connectors in a different angular position results in the same contact pairs being in electrically conductive relationship, Always the desired electrical paths are established regardless of how the connectors are being coupled. A cumbersome alignment of the contact pairs is obsolete.
Finally, the first and/or the second connector has or have at least one guide. Compared with a mechanical guide of the prior art, the guide according to the present invention fulfils a different task in a different state of the connector assembly, namely in a coupled state of the connector assembly. In contrast to the prior art, the guide according to the present invention is arranged such that in a coupled state of the connector assembly it prevents a displacement of the connectors relative to each other which would result in a loss of the electrically conductive relationship of the contacts of the first connector with the corresponding contacts of the second connector.
Further advantages, features, characteristics and aspects of the present invention result from the claims and the following description of preferred embodiments of the present invention by means of examples only with reference to the accompanying drawings, in which

Fig. 1: illustrates a perspective view of a connector assembly in an uncoupled state in accordance with a first embodiment of the present invention;
Fig. 2: schematically illustrates a cross-sectional view along line II-II in Fig. 1 of a connector of the proposed connector assembly in accordance with the first embodiment of the present invention;
Fig. 3: schematically illustrates a front view of a connector of the proposed connector assembly in accordance with a second embodiment of the present invention;
Fig. 4: schematically illustrates a cross-sectional view similar to Fig. 2 of a connector of the proposed connector assembly in accordance with a third embodiment of the present invention.

It will be noted that throughout the appended drawings, like features are identified by like reference numerals.
Fig. 1 illustrates a first embodiment of the present invention in an uncoupled state in a perspective view. The present invention provides a connector assembly 1 for electrically connecting a first electrical or electronic item (not shown) to a second electrical or electronic item (not shown).
For example, the proposed connector assembly 1 connects a portable device like a laptop, a tablet PC or a portable display to a power supply, so that a rechargeable battery of the mobile device can be recharged. In another example, the proposed connector assembly 1 connects household appliances like an electric iron, a kettle or a toaster to a power supply. In a further example, the proposed connector assembly 1 electrically connects a loudspeaker of a loudspeaker set of a home entertainment system to another loudspeaker of the loudspeaker set. However, many other examples are within the scope of the present invention.
The connector assembly 1 comprises a first connector 2, positioned on the left in Fig. 1, having a first magnetic assembly 3 with at least one magnetic element. The first connector 2 has at least two contacts 4, namely in fact the contacts 4',4", of an electrically conductive material. The contacts 4 are electrically connected to the first electrical or electronic item (not shown) and electrically insulated from each other by an insulating material, which is, for example, made of plastics.
The connector assembly I further comprises a second connector 5, positioned on the right in Fig. 1, having a second magnetic assembly 6 with at least one magnetic element. The second connector 5 has at least two contacts 7, namely in fact also three contacts 7, of an electrically conductive material. The contacts 7 are electrically connected to the second electrical or electronic item (not shown) and electrically insulated from each other by an insulating material, which is, for example, made of plastics.
The contacts 4 of the first connector 2 are maintained in electrically conductive relationship with the contacts 7 of the second connector 5 by magnetic attraction between the first and second magnetic assembly 3,6. The magnetic attraction is configured to be sufficiently strong to reliably complete an electrical or electronic circuit by the contacts 4 and the contacts 7 and to ensure a rugged connection of the two connectors 2,5. Simultaneously, the magnetic attraction is configured to be small enough so that the resulting magnetic field does not interfere with the connected electrical or electronic items, e.g. a power supply, or electromagnetic elements thereof. The magnetic attraction force between the connectors 2,5 can be configured as desired for a specific implementation.
The connector assembly 1 is designed such that in a coupled state it is resistant to vibration, water or other contaminants, and pressure to a certain extent. Furthermore, the connector assembly 1 assures protection against electric shock. The connector assembly 1 has a low contact resistance between the contacts 4,7 and high insulation value outside the area of the contacts 4,7.
The illustrated and preferred embodiment in Fig. 1 shows a first characterizing feature of the present invention, namely that the contacts 4 of the one connector 2 are designed as concentric tracks 4.
Preferably, the concentric tracks 4 are at least substantially flat with an axial extension below 10 mm, especially preferred below 5 mm. The maximum distance between the perimeter of the outermost concentric track 4 and a common centre of the concentric tracks 4 is preferably below 20 mm, particularly preferred below 10 mm.
As a good contact making and low contact resistance are most important, the concentric tracks 4 are preferably made of electrically conductive materials like brass, copper, silver, palladium or gold. Especially preferred are concentric tracks 4 with gold plating.
According to a further characterizing feature of the present invention, the contacts 7 of the other connector 5 are positioned such that in a coupled state of the connector assembly 1 each single contact 7 of the other connector 5 abuts on a different contact 4 of the one connector 2. Thus, each contact pair establishes a separate electrical path in a coupled state of the connector assembly 1.
According to another characterizing feature of the present invention, the two connectors 2,5 can, in principle, be coupled in more than two angular positions relative to each other and to a central axis 8 common to the concentric tracks 4. The connector assembly 1 is designed such that coupling the connectors 2,5 in a different angular position results in the same pairs of contacts being in electrically conductive relationship. The pairs of contacts do not require cumbersome alignment during the coupling process.
The geometric shape of a concentric track 4 is not necessarily circular or round. In fact, it is essential that it fulfils two criteria.
On the one hand, the geometric shapes of the concentric tracks 4 have to share the same centre of gravity (condition for concentricity). In Fig. 1 the common centre of gravity is the penetration point of the central axis 8 and the concentric tracks 4.
On the other hand, the geometric shapes of the concentric tracks 4 have to allow the two connectors 2,5 to be coupled in more than two angular positions relative to each other and to the central axis 8. Possible shapes fulfilling this criterion are, for example, regular polygons with more than two edges, such as a regular hexagon. A regular polygon with n edges has rotational symmetry of order n and therefore n possible angular positions for coupling the connectors 2,5, wherein the central axis 8 is the axis of rotational symmetry. Suitable regular polygon shapes can be convex or star-shaped.
According to another characterizing feature of the present invention the first connector 2 has at least one guide 9 and/or the second connector 5 has at least one guide 10 which are arranged such that in a coupled state of the connector assembly 1 they prevent a displacement of the connectors 2,5 relative to each other which would result in a loss of the electrically conductive relationship of a contact 4 of the first connector 2 with the corresponding contact 7 of the second connector 5. This feature is essential to ensure that a certain contact pair is not electrically separated in a coupled state of the connector assembly 1. In Fig. 1, the guide 9 is shown to protrude from the first connector 2 like a lip, whereas the second connector 5 does not have a separate guide, because its outer surface defines the corresponding guide 10. However, the guide 9 of the first connector 2 can also be designed as a recess which is engaged with the guide 10 of the second connector 5. It will be appreciated by a person skilled in the art that a number of guiding techniques can be used to prevent unwanted displacement.
In the preferred embodiment shown in Fig. 1 the concentric tracks 4 are designed as circular rings 4' and a central circle 4". In principle, the concentric tracks 4 comprise one central circle 4" at most. As the connectors 2,5 each have at least two contacts, the contacts 4 of the one of the connectors 2,5 comprises at least one circular ring 4', if any. A circular ring 4' is here defined as the area between the circumferential lines of two concentric circles.
In this case, the connector assembly 1 is preferably designed such that in a coupled state of the connector assembly 1 the two connectors 2,5 are rotatable about the central axis 8 in opposite directions relative to each other. In the preferred embodiment shown in Fig. 1 the connector assembly 1 is designed such that in a coupled state of the connector assembly 1 the two connectors 2,5 are rotatable about the central axis 8 in opposite directions relative to each other through an angle of 360° (in fact without limitation).
This feature simplifies the handling and avoids damage of the connector assembly 1. In a coupled state of the connector assembly 1, any force in a slanting direction, e.g. when the connector assembly 1 is inadvertently exposed to a non-axial force, is transformed into a rotational force leading to a rotation of the connectors 2,5 relative to each other and to the central axis 8.
The electrically conductive relationship between the contacts pairs is maintained and the connector assembly 1 is not damaged.
Fig. 3 schematically illustrates a second embodiment of the present invention in a front view of the connector 2 of the proposed connector assembly 1. In this particularly preferred embodiment at least one of the circular rings 4' is laterally divided into at least two circular sectors 4"', which are electrically connected to the one of the electrical or electronic items 11 and electrically insulated from each other. Thus, it is possible to electrically connect more contacts pairs and increase the number of electrical paths without increasing the overall size of the connector assembly 1. However, dividing the circular rings 4' into circular sectors 4'" decreases the contact area of the corresponding contact pairs and the angle through which the connectors 4' can potentially be rotated in opposite directions relative to each other in a coupled state of the connector assembly 1.
As indicated in Fig. 3, one of the electrical or electronic items 11 can be a printed circuit board. Of course, the two connectors 2,5 can be connected to other electrical or electronic items.
In Fig. 3 it can be seen that the outermost circular ring 4' is divided into three sectors 4"' which are separated by insulators 12. In this case, the connector assembly 1 can be designed such that in a coupled state of the connector assembly 1 the two connectors 2,5 are rotatable about the central axis 8 in opposite directions relative to each other through an angle of approximately 85°. Of course, other embodiments, e.g. with a circular ring 4' divided into two semi-circular sectors 4"', are possible and within the scope of the present invention.
It should be noted that by dividing the circular rings 4' into circular sectors 4"' coupling the connectors 2,5 in a different angular position can result in different contact pairs being in an electrically conductive relationship.
Preferably, the contacts 7 of the other of the connectors 5 are positioned such that the sum of the distances between each pair of contacts 7 reaches its maximum, wherein in a coupled state of the connector assembly 1 the contacts 7 of the other of the connectors 5 centrally abut on the concentric tracks 4 of the one connector 2. The distance between a pair of contacts 7 is defined here as the length of the shortest straight line connecting the perimeters of two respective contacts 7. By means of this feature the center of mass of the other of the connectors 5 can be influenced such that it is as close as possible to the central axis 8. Thus, the electrically conductive relationship between the two connectors 2,5 is more rugged.
Preferred embodiments according to this feature are shown in Fig. 1, 2 and 4. For example in Fig. 2, three contacts 7 are illustrated. The outermost of the contacts 7 is not positioned on the left side of the other of the connectors 5, but on the right side, so as to be as far as possible away from the leftmost of the contacts 7 in Fig. 2. Fig. 4 shows a preferred positioning of the contacts 7 according to the lastly defined feature in case of five contacts 7.
In these two particularly preferred embodiments, the lastly defined feature is fulfilled if the contacts 7 of the connector 5 are positioned in a straight line. However, in other embodiments of the present invention the contacts 7 can be differently positioned than in a straight line.
Preferably, the contacts 7 of the other connector 5 are designed as pins, which preferably are spring-loaded, particularly loaded by springs 13. The springs 13 arc engaged with a bottom side of the pins. The tops of the pins are preferably pointed.
The springs 13 can be made of an electrically conductive material. In this case, the springs 13 can be connected by wires 14 to the associated electrical or electronic item (not shown in Fig. 4).
As can be seen in Fig. 2 and 4 the pins are preferably located in passages or slots in an insulator 15. Typically, this apparatus will be manufactured by injection-molding around the pins. The pins of the connector 5, but also the contacts 7 in general, and the corresponding magnetic assembly 6 can be protected by a non-conductive shell 16.
Preferably, the pins protrude all other components of the other of the connectors 5, e.g. the insulator 15, the magnetic assembly 6 or the shell 16, in an uncoupled state of the connector assembly 1. When coupling the two connectors 2,5, the pins are pushed into the passages or slots by the concentric tracks 4, as the springs 13 are compressed. When releasing the two connectors 2,5, the springs 13 expand and the pins are pushed back again. Neither in a coupled state nor in an uncoupled state of the connector assembly 1, the pins have to abut on a common plane, so, for example, they can have different heights.
In case the connector assembly 1 is used to connect an electric or electronic item to a power supply, the concentric tracks 4 preferably are recessed relative to each other and the central axis 8. According to the design of the concentric tracks 4, the tops of the pins of the other connector 5 are designed to fit in a corresponding recess formed by the concentric tracks 4. Thus, protection against electric shock and insulation of the contacts 7 against each other are improved. For example, in a connector assembly 1 for providing single-phase electric power and having three concentric tracks 4, the concentric track 4 connected to a live wire can be designed as central circle 4", which has the greatest axial recess, the concentric track 4 connected to a neutral wire can be designed as circular ring 4', which has an axial recess smaller than the recess of the central circle 4", and the third concentric track 4, preferably the outermost concentric track 4, can be designed as circular ring 4', which is not recessed and which provides electrical earthing of the connector assembly 1.
In the preferred embodiment of the present invention shown in Fig. 1, the magnetic assemblies 3,6 are positioned such that they abut on each other in a coupled state of the connector assembly 1, This arrangement enables a simple construction of the connector assembly 1 and a rugged connection of the two connectors 2,5.
Preferably, the magnetic assembly 3 of the one connector 2 comprises one magnetic element which is designed as circular ring surrounding the contacts 4 of the one connector 2 and/or the magnetic assembly 6 of the other connector 5 comprises one magnetic element which is designed as hollow cylinder surrounding the contacts 7 of the other connector 5. This arrangement is one example allowing the two connectors 2,5 being rotatable about the central axis 8 in opposite directions relative to each other through an angle of 360° or practically without limitation.
It is particularly preferred to position the magnetic assembly 6 of the other connector 5 within the shell 16.
Concerning the magnetic assemblies 3,6, the magnetic elements of both magnetic assemblies 3,6 are preferably designed as magnets, particularly as permanent magnets, arranged such that the magnetic assemblies 3,6 magnetically attract each other.
In an alternative embodiment of the present invention, one of the magnetic assemblies 3,6 is composed of at least one magnet, preferably a permanent magnet, and the other of the magnetic assemblies 6,3 is composed of a magnetic material, preferably a ferromagnetic material, particularly custom grade steel.
Various other arrangements of the magnetic assemblies 3,6 are possible and would be within the abilities of a person skilled in the art. They can be incorporated into the connector assembly 1, without departing from the intended scope of the appended claims.
In particular, single features of the presented embodiments of the present invention can be arbitrarily combined.

List of reference signs:

1 connector assembly
2 first connector
3 first magnetic assembly (first connector)
4 contacts (first connector)
4' circular ring (first connector)
4" central circle (first connector)
4"' circular sector (first connector)
5 second connector
6 second magnetic assembly (second connector)
7 contacts (second connector)
8 central axis (first connector)
9 guide (first connector)
10 guide (second connector)
11 printed circuit board
12 insulator (first connector)
13 spring (first connector)
14 wire
15 insulator (second connector)
16 shell

Claims

A connector assembly (1) for electrically connecting a first electrical or electronic item to a second electrical or electronic item, comprising a first connector (2) having a first magnetic assembly (3) with at least one magnetic element and having at least two contacts (4) of an electrically conductive material, electrically connected to one of the first and second electrical or electronic items and electrically insulated from each other, and
a second connector (5) having a second magnetic assembly (6) with at least one magnetic element and having at least two contacts (7) of an electrically conductive material, electrically connected to the other of the first and second electrical or electronic items and electrically insulated to each other,
wherein the contacts (4) of the first connector (2) are maintained in electrically conductive relationship with the contacts (7) of the second connector (5) by magnetic attraction between the first magnetic assembly (3) and second magnetic assembly (6),
characterized in that
the contacts (4) of one of the connectors (2) are designed as concentric tracks (4),
the contacts (7) of the other of the connectors (5) are positioned such that in a coupled state of the connector assembly (1) each single contact (7) of the other connector (5) abuts on a different contact (4) of the one connector (2), the two connectors (2,5) can, in principle, be coupled in more than two angular positions relative to each other and to a central axis (8) common to the concentric tracks (4) with always the same pair of contacts (4,7) being in electrically conductive relationship in a coupled state of the connector assembly (1), and
the first connector (2) has at least one guide (9) and/or the second connector (5) has at least one guide (10) which are arranged such that in a coupled state of the connector assembly (1) they prevent a displacement of the connectors (2.5) relative to each other which would result in a loss of the electrically conductive relationship of a contact (4) of the first connector (2) with the corresponding contact (7) of the second connector (5).
The connector assembly according to claim 1, characterized in that the concentric tracks (4) are designed as circular rings (4') and/or a central circle (4"), wherein the concentric tracks (4) comprise one central circle (4") at most.
The connector assembly according to claim 2, characterized in that the connector assembly (1) is designed such that in a coupled state of the connector assembly (1) the two connectors (2,5) are rotatable about the central axis (8) in opposite directions relative to each other.
The connector assembly according to claims 2 or 3, characterized in that at least one of the circular rings (4') is laterally divided into at least two circular sectors (4"'), which are electrically connected to the one of the electrical or electronic items and electrically insulated from each other.
The connector assembly according to any one of the preceding claims, characterized in that
the contacts (7) of the other of the connectors (5) are positioned such that the sum of the distances between each pair of contacts (4,7) reaches its maximum.
The connector assembly according to any one of the preceding claims, characterized in that
the contacts (7) of the other of the connectors (5) are positioned in a straight line.
The connector assembly according to any one of the preceding claims, characterized in that
the contacts (7) of the other of the connectors (5) are designed as pins, which preferably are spring-loaded.
The connector assembly according to any one of the preceding claims, characterized in that
in a coupled state of the connector assembly (1) the magnetic assemblies (3,6) arc positioned such that they abut on each other.
The connector assembly according to any one of the preceding claims, characterized in that
the magnetic assembly (3) of the one of the connectors (2) comprises one magnetic element which is designed as circular ring surrounding the contacts (4) of the one of the connectors (2) and/or
the magnetic assembly (6) of the other of the connectors (5) comprises one magnetic element which is designed as hollow cylinder surrounding the contacts (7) of the other of the connectors (5).
The connector assembly according to any one of the preceding claims, characterized in that
the magnetic elements of both magnetic assemblies (3,6) are designed as magnets, preferably permanent magnets.
The connector assembly according to any one of claims 1 to 9, characterized in that
one of the magnetic assemblies (3) comprises at least one magnet, preferably a permanent magnet, and
the other of the magnetic assemblies (6) comprises a magnetic material, preferably a ferromagnetic material.