WO2010119302A1

WO2010119302A1 - Magnetic connector and a data communication system using the magnetic connector

Info

Publication number: WO2010119302A1
Application number: PCT/HU2010/000043
Authority: WO
Inventors: Balázs SELLER
Original assignee: Protecta Elektronikai Kft.
Priority date: 2009-04-16
Filing date: 2010-04-14
Publication date: 2010-10-21

Abstract

The invention is a magnetic connector (10, 10") for enabling a data communication through a casing of an apparatus (11), the magnetic connector comprising - a connecting surface (12, 12'), - positioning magnets (13) arranged at the connecting surface (12, 12'), and - electro-magnetic coils (T1, T2; T11, T21) suitable for realising the data communication, the electro-magnetic coils (T1, T2; T11, T21) being arranged at the connecting surface (12, 12') with their axes essentially perpendicularly to the connecting surface (12, 12'). According to the invention the electro-magnetic coils (Tl, T2; T1 \ T21) are air core coils having a middle diameter (Dm) and an axial length (L), the middle diameter (Dm) being at least double of the axial length (L). Further, the invention is a data communication system using the above magnetic connector.

Description

MAGNETIC CONNECTORAND A DATA COMMUNICATION SYSTEM USING

THE MAGNETIC CONNECTOR

TECHNICAL FIELD

The invention relates to a magnetic connector and a data communication system making use thereof, enabling electronic as well as digital devices and apparatuses to be connected to a communication network through a casing. According to the invention, the information technology and data communication link may be established in such a way, that the casing of the device or apparatus remains continuous.

BACKGROUND ART

Digital devices and apparatuses, which are to be connected to IT networks, e.g. to a personal computer, suffer the general problem, that the casing is discontinuous at the actual point of connection, whereby the apparatus looses its resistance to dust, water and electric noise.

In order to eliminate the above problem, there is a known solution, wherein data communication is transmitted via a wireless network by means of high frequency radio waves, nevertheless, in the case of industrial, e.g. electric substation environments it has a great disadvantage, namely that it is unprotected against electric noise.

There is yet a further known solution, wherein the apparatus is connected into communication by means of a light conducting optical fiber. In this case, however, a separate unit is required for transforming the light into an electric signal.

There are also other known solutions, wherein energy and/or data is transmitted through the casing by inductive means. Such connectors are disclosed e.g. in US 4,838,797, US 4,844,582, US 2007/0259536 A1 , US 7,331 ,793 B2, US 7,467,948 B2, EP 1 647 038 B1 , WO 2006/067528 A2, WO 2007/079501 A2 and WO 2009/021025 A2 The above referenced US 7,331 ,793 B2 patent document discloses a magnetic connector suitable for performing data communication through the casing of an apparatus, and comprising a connecting surface, positioning magnets arranged at the connecting surface, as well as electro-magnetic coils suitable for performing data communication and also arranged at the connecting surface and having an axis essentially perpendicular to the connecting surface. The disadvantage of this known solution is that it requires - due to the low-diameter electro-magnetic coils - extremely precise positioning, which cannot be provided by means of the positioning permanent magnets. It is a further disadvantage, that the operation of the connector requires an extra power supply, and therefore cannot be arranged universally as a 'passive' element having no power supply.

DESCRIPTION OF THE INVENTION

It is an object of the invention to provide a magnetic connector and a data communication system making use thereof, which are exempt of the disadvantages of the prior art solutions. Further, it is an object of the invention to provide a data connector and a system, which are suitable for establishing a high- frequency range connection through a casing by means of regular cables and connectors without requiring external auxiliary power supply. Yet another object is to provide a magnetic connector at low cost and made up of simple components.

These objects have been achieved according to the invention by means of the magnetic connector according to claim 1 as well as by means of the data communication system according to claim 7. The preferred embodiments of the invention are defined in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will be described hereunder with reference to drawings, where

Fig. 1 is a schematic view of a data communication system according to the invention comprising magnetic connectors, Fig. 2A is a schematic front view of a magnetic connector according to the invention,

Fig. 2B is a schematic side view in section of the magnetic connector according to Fig. 2A₁ and Fig. 3 is a schematic sectional side view of an electro-magnetic coil included in the magnetic connector according to Figs. 2A and 2B.

MODES OF IMPLEMENTATION OF THE INVENTION

The magnetic connectors according to the invention have been elaborated in order to perform data communication through a casing of an electronic or digital device or apparatus. By way of example, the invention may be advantageously applied in high-voltage protection apparatuses, which generally are arranged in industrial environments highly exposed to electro-magnetic noise, in rooms dedicated for the apparatuses. Such protection apparatuses may record a large amount of information and data which need to be read from the apparatuses for diagnostic or checking purposes. There may furthermore be a need to modify the inner parameters or software of such protecting apparatuses, i.e. to load various data into the memory of the apparatuses.

In order to fulfil the above objects, it is necessary to establish a data communication link with the apparatuses. In an industrial environment, it is of extraordinary importance that the casing of the apparatuses is not discontinuous due to the data communication demand, in other words, that the casing meets the requirements of e.g. dust and water resistance. The solution according to the invention has been elaborated primarily for these purposes, nevertheless, it may be applied in any other environment, where a communication link is to be established with apparatuses having a continuous casing.

The data communication system schematically shown in Fig. 1 comprises two magnetic connectors 10, 10'. A first magnetic connector 10 of these is advantageously connectable via an ethernet cable 16 directly to a computer device 18 by means of a conventional e.g. type RJ45 connector. This first magnetic connector 10 is formed to be placed onto a casing of an electronic device 11. Underneath the casing of the electronic device 11 , the second magnetic connector 10' is arranged. The first magnetic connector 10 is positioned in an appropriate location of the casing by means of positioning magnets not indicated in the Fig., preferably by means of permanent magnets. The second magnetic connector 10' is formed in a mirror-arrangement to the magnetic connector 10 within the apparatus 11 , ad has appropriate positioning contra-magnets.

Accordingly, the data communication system according to the invention establishes data communication through the casing between the electronic device

11 and the computer device 18.

In a way as indicated in Figs. 2A and 2B, the magnetic connector 10 comprises a connecting surface 12, positioning magnets 13 arranged at the connecting surface

12 as well as electro-magnetic coils T1 and T2 suitable for establishing data communication and also being arranged at the connecting surface 12, and having an axis essentially perpendicular to the connecting surface 12. The magnetic connector 10' arranged within the apparatus 11 also comprises a connecting surface 12', positioning magnets 13, as well as electro-magnetic coils T1' and T2'.

The coils T1 , T2, T1', T2' according to the invention are air core coils having as seen in Fig. 3 a middle diameter Dm, which is at least double of their axial length L.

Dimensioning of the electro-magnetic coils T1 , T2, TV, T2' according to the invention is of extraordinary significance, since our experiments leading to the invention have proved that the simple and effective positioning of the magnetic connector 10, 10' by means of permanent magnets can only be realised when permitting a certain tolerance. The permanent magnetic positioning - preferably usable for the purposes of the invention - are capable of realising positioning typically with a tolerance of approx. 1 to 2 mm. If the electro-magnetic coils used for data communication purposes were relatively low in diameter, a relatively small positioning inaccuracy would influence the speed and reliability of data communication in a great extent. If, however, the used coils are relatively flat and of a great in diameter, positioning inaccuracies will not cause the aforementioned disadvantages. Our experiments have proved that the inventive advantages are present if the middle diameter Dm of the air core coils is at least double of the axial length L of the coils.

Dimensioning of the electro-magnetic coils T1 , T2; TV, T2¹ as in the invention has not been applied in the relevant prior art technology for the following reasons. It is a general engineering thinking to aim at minimising the coil diameter in order to reduce the space demand of the connector, furthermore, to focus on increasing the axial length of the coils so as to achieve the strongest possible inductive coupling. In this way, the recognition as per the invention is opposite to the general engineering concept.

The forming of the coils with an air core according to the invention means that no iron-core or ferro-magnetic materials are used therein; in other words, various non- ferro-magnetic materials may be included in the air core in a given case. It is the advantage of the air core arrangement, that the inductive coupling required for the data communication will not significantly be influenced by the size of the air gap, or an inaccuracy of the positioning. The total resistance of the inductive coupling is made up of the respective resistance of the coils and the resistance of the air core. In the case of iron-core coils, the resistance of the coils is practically zero, which increases the specific weight of air core resistance within the total resistance. In the case of air core coils, the coils yet themselves have significant resistance, by means of which the total resistance is influenced to a small extent, only, by the air gap resistance.

The magnetic connector 10, 10' according to the invention is preferably formed for establishing an ethernet data communication, and is connected to an ethernet communication device in such a way that it comprises two electro-magnetic coils T1, T2 or TV, T2¹. One of the two coils is connected to one of the conduit-pair 14, 14' of the ethernet communication device, while the other is connected to the other conduit-pair 15, 15' of the ethernet communication device.

By means of this preferred embodiment, the inventive object of providing for data communication without incremental power supply in a simple way is achieved. In order to achieve that resistance of the ethernet cable 16 does not influence the efficiency of the data communication, as well as to achieve that the change of the resistance of the cable 16 does not cause data communication uncertainties, the terminals of the electro-magnetic coils are each provided with a matching resistance R, the uniform value of each being between 0,5 and 5 Ohm, preferably having the value of 1 Ohm. The same applies to the magnetic connector 10' located within the apparatus 11.

In a way as indicated in Fig. 1 , the ethernet communication device connected to the computer device 18 is the ethernet cable 16, while the ethernet communication device located within the apparatus 11 is an ethernet circuit 17, preferably an ethernet switch IC.

Our experiments concluded that it is advantageous, if the electro-magnetic coils T1 , T2; T1', T2' have a middle diameter (Dm) of between 5 and 20 mm, preferably 12 mm, an axial length (L) of between 1 and 2.5 mm, preferably 2 mm, and an effective number of windings of between 6 and 30, preferably 20.

By means of the above dimensioning, the inventive objects will be achieved in a simple and effective manner. Here, effective number of windings shall refer to the inductive properties exhibited according to the number of windings. Accordingly, each of the coils T1 and T2 preferably have 20 windings respectively, while the coils TT and T2' center-tapped to match the commercially available ethernet switch IC construction have 2x10 windings, i.e. a total of 20 effective windings, each. In this way, 1 :1 signal transmission can preferably be implemented.

The minimum diameter of the coils is determined by the consideration that the positioning achievable with a few mm tolerance shall not cause impairment of data communication. The maximum diameter is determined by portability, practicality and space demand. The preferred coil parameters defined hereabove had been concluded in consideration of these factors.

Accordingly, the magnetic connector 10 shown in Fig. 2A comprises two positioning magnets 13, preferably arranged as permanent magnets, as well as electro-magnetic coils T1 and T2. The positioning magnets 13 are preferably arranged in such a way that at least one electro-magnetic coil T1 is arranged therebetween. The advantage of this arrangement is that it will improve the certainty and accuracy of positioning for the enclosed coils. Due to the inductive separation of the coils T1 and T2, it is advantageous if positioned at a greater distance from each other, for example by placing one positioning magnet 13 in between the two coils T1 and T2, as shown in the preferred embodiment.

The magnetic connector 10 is preferably arranged in a housing 19, a thinned front cover of which forms the connecting surface 12. The connecting surface has a width of advantageously not more than 0.5 mm, preferably 0.1 mm. Of course, the housing 19 is dust and water resistant. The coils T1 and T2 are arranged on an printed circuit board 20 located within the housing 19. The cable 16 is also connected to the printed circuit board 20.

In a way as shown in Fig. 3, the electro-magnetic coils, by way of example the electro-magnetic coil T1 is preferably formed on a plastic reel body 21. The flared side of the reel body 21 faces the printed circuit board 20, while the electromagnetic coil T1 faces the connecting surface 12. It is an advantage of this arrangement, that the elements establishing the electro-magnetic data communication are closer to the casing of the apparatus 11.

Thus, by means of the data communication system according to the invention, a solution is provided, wherein the magnetic connector 10 can be connected via an universal ethernet connector to any computer device 18, preferably to a personal computer. In order to establish the communication no special hardware or software is required, and communication can be made irrespective of the manufacturer, platform, or operating system via the ethernet connector. In the course of the communication, the computer device 18 sees a standard ethernet network, through which a 10 Mbit/s data rate bandwidth has been achieved by means of the inventive solution. Communication on a personal computer is possible to be carried out by means of a general browsing software.

According to the invention, we have found that up to a cable distance of approx. 20 meter, the standard UTP cable will not influence the matching of the inductive coupling. According to the invention, preferably an approx. 2 meter cable length is advantageous between the computer device 18 and the magnetic connector 10.

By eliminating the demand for auxiliary power, it can be achieved that communication is established irrespective of the given electric network. Another advantage of eliminating the need for an additional power supply is that the inventive data communication is usually required in case of malfunction, namely in such cases when power supply is at fault, or stalls. Therefore, unobstructed data communication can be realised in such cases just as well.

The arrangement according to the invention can also be considered as applying an air core coiling with an air gap separation, the air gap of which geometrically coincide with the plastic foil covering the front of the device. In this way, the two half-coils T1\ T2' are comprised by the apparatus, and the half-coils T1 , T2 are in a magnetically fixed coupling box mounted to the end of the UTP cable 16. The diameter of the coils is selected in such a way, that a positioning inaccuracy resulting from the magnetic fixing does not cause any transmission fault.

The number of windings and the value of impedance matching resistances are chosen so as to be able to ensure the coupling without any external power supply, by means of the energy resultant from the operation of the ethernet network, through an air gap of 0,1 to 1 mm.

The invention, of course, is not limited to the above detailed embodiments, but further modifications, variations are possible within the scope defined by the claims.

Claims

1. A magnetic connector (10, 10') for enabling a data communication through a casing of an apparatus (11), the magnetic connector comprising - a connecting surface (12, 12'),

- positioning magnets (13) arranged at the connecting surface (12, 12'), and

- electro-magnetic coils (T1, T2; TV, T2¹) suitable for realising the data communication, the electro-magnetic coils (T1 , T2; TV, T2¹) being arranged at the connecting surface (12, 12') with their axes essentially perpendicularly to the connecting surface (12, 12'), c h a r a c t e r i s e d in that the electro-magnetic coils (T1 , T2; TV, T2¹) are air core coils having a middle diameter (Dm) and an axial length (L), the middle diameter (Dm) being at least double of the axial length (L).

2. The magnetic connector according to claim 1 , characterised in that it is suitable for realising an ethernet data communication, and is connected to an ethernet communication device in such a way, that it comprises two electro-magnetic coils (T1 , T2; TV, T2¹), one of which being connected to a conduit-pair (14, 14') of the ethernet communication device, while the other is connected to another conduit- pair (15, 15') of the ethernet communication device.

3. The magnetic connector according to claim 2, characterised in that each of the terminals of the electro-magnetic coils (T1, T2; TV, T2¹) are fitted with a matching resistance (R), which all have a value of between 0,5 and 5 Ohm, preferably 1 Ohm.

4. The magnetic connector according to claim 2, characterised in that the ethernet communication device is an ethernet cable (16) or an ethernet network (17), preferably an ethernet switch IC.

5. The magnetic connector according to any of claims 1 to 4, characterised in that the electro-magnetic coils have a middle diameter (Dm) of between 5 and 20 mm, preferably 12 mm, an axial length (L) of between 1 and 2.5 mm, preferably 2 mm, as well as an effective number of windings of between 6 and 30, preferably 20.

6. The magnetic connector according to any of claims 1 to 5, characterised in that the positioning magnets (13) are permanent magnets, wherein at least one of the electro-magnetic coils (T1 , T2; TT, T2¹) is arranged between them.

7. A data communication system for enabling a data communication between an electronic apparatus (11) and a computer device, through the casing of the electronic apparatus (11), c h a r a c t e r i s e d by comprising magnetic connector(s) (10,10') according to any of claims 1 to 6.

8. The data communication system according to claim 7, characterised by comprising a first magnetic connector (10) connectable directly to the computer device (18) via an ethernet cable (16) and placeable onto the casing of the electronic apparatus (11), and a second magnetic connector (10') located within the casing of the electronic apparatus (11).