DE102016201253A1 - Device for wireless energy supply and data transmission for a transponder in a rotatable system with low-energy applications - Google Patents

Abstract

Device 100 for wireless power supply and data transmission for a transponder in a rotatable system. The device comprises a shaft 110, a coil carrier 130, which is arranged at a distance from the shaft 110, and a primary coil 135, wherein the primary coil 135 is arranged on the coil carrier 130. The primary coil 135 generates a magnetic field in which a secondary coil 115 can rotate. The secondary coil 115 is disposed on the shaft 110. According to the invention, the primary coil 135 and the secondary coil 115 are spaced apart from one another and arranged concentrically around the shaft relative to one another such that signals and energy can be transmitted.

Description

The present invention relates to a device for wireless energy supply and data transmission for a transponder in a rotatable system with low-power applications, in particular for an RFID tag or NFC tag. Furthermore, the invention relates to a sensor bottom bracket with such a device and a bicycle with such a sensor bottom bracket.

A transponder is a radio-based communication device that can record incoming signals and answer or forward. The term transponder is made up of the terms transmitter and responder.

Passive transponders derive the energy for communication and processing of processor instructions from an electromagnetic field of corresponding writing and reading units, which are brought into short distance to the transponder for this purpose. Passive transponders do not require their own power supply.

By contrast, active transponders have their own power supply, for example a battery or a connection to a power grid. Thus, active transponders can manage larger data memories, bridge larger radio ranges or operate further sensors integrated on or at the transponder.

A well-known passive transponder type is the so-called RFID tag (RFID stands for "Radio Frequency Identification" or "Radio Frequency Identification"). It consists of a coupling element, an antenna coil or dipole antenna, and a microprocessor. The RFID tag wins the supply voltage, as mentioned above, from the electromagnetic fields emitted by the RFID readers and writers. It is limited to a generally maximum radio range of up to one meter, with simultaneous energy transfer. Therefore, the RFID tag is typically used in the identification of objects or smart cards for access control systems.

Another well-known transponder type is the NFC tag (NFC stands for near field communication). It is based on RFID technology and is specifically designed to secure wireless data transmission over very short distances, ie a maximum of 10 cm, generally less than 4 cm. The NFC tag is used in particular for cashless payment of small amounts. It is typically integrated into bank cards or mobile phones.

Transponders, in particular the widespread RFID and NFC tags, can therefore be supplied with energy by the electromagnetic field of a writing and reading device. For this purpose, the writing and reading devices and the transponders are brought into spatial proximity. The exchange of data and the transfer of energy thus take place in an opposite, planar and a substantially motionless arrangement.

In rotating or rotatable systems, such as a bearing, however, energy is generally transmitted using slip rings or similar contact-based methods, for example, to supply sensors in a sensor bottom bracket for detecting torques.

The object of the present invention is to provide a device for power supply and data transmission for a transponder in a rotatable system which can transmit data and energy completely contactlessly between the rotatable components. Furthermore, the device should require the smallest possible space and be suitable in particular for the application of RFID or NFC tags.

This object is achieved according to the invention first with a device for wireless power supply and data transmission for a transponder in a rotatable system according to independent claim 1. The device comprises a shaft and a coil carrier, which is arranged at a distance from the shaft. Furthermore, the device comprises a primary coil, which is arranged on the coil carrier and generates a magnetic field, and a secondary coil, which is arranged on the shaft. The secondary coil is rotatable in the magnetic field. Further, the primary coil and the secondary coil are spaced from each other and arranged concentrically around the shaft to each other that signals and energy can be transmitted.

In one embodiment of the device according to the invention, the coil carrier is arranged concentrically around the shaft.

In one embodiment of the device according to the invention, the primary coil is a transmitting coil and the secondary coil is a receiving coil.

The secondary coil can rotate in the magnetic field and thus enables the continuous transmission of signals and energy. In a rotating system, therefore, no dead spots occur during the transmission of data and energy. In particular, the transponder and optionally further sensor elements arranged on the shaft can thus be permanently supplied with energy. In other words In other words, the device according to the invention makes it possible to convert the previously known passive transponders into now active transponders in a round arrangement, without having to resort to a battery or an external power source.

In a further embodiment, the device comprises at least one ferrite. The at least ferrite is arranged on the secondary coil and / or on the primary coil. Particularly preferably, the at least one ferrite is arranged between the shaft and the secondary coil. Also preferably, the at least one ferrite is arranged between the coil carrier and the primary coil. The at least one ferrite advantageously aligns the magnetic field, whereby eddy current losses can be reduced and higher efficiency in the power supply and data transmission can be achieved. Thus, it is possible to make the primary and / or secondary coil smaller. This has the further advantage that even rotating or rotatable systems can be equipped with only small space with the device according to the invention.

In a further embodiment, the primary coil and / or the secondary coil are formed as an annular coil, which are arranged for example concentrically around the shaft.

In a further embodiment, the primary coil and / or the secondary coil are formed as a planar rectangular coil, which are arranged for example concentrically around the shaft. Such a coil arrangement can be created, for example, advantageously via printed conductor tracks. Thus, tracks can be mounted on flexible supports and then arranged concentrically around the shaft.

In one embodiment of the device according to the invention, the transponder is an RFID tag. In an alternative embodiment of the device according to the invention, the transponder is an NFC tag.

In a further embodiment of the device according to the invention, the transponder comprises a data memory.

In a further embodiment of the device according to the invention, the transponder comprises a processor.

In a further embodiment of the device according to the invention, the processor is a microprocessor or a microcontroller.

In a further embodiment of the device according to the invention, the transponder comprises an energy control unit. The energy control unit can in particular be configured for the energy management in the case of a permanent power supply and / or the transmission of the energy to other power consumers, such as sensor elements.

Further aspects of the present invention are a sensor bottom bracket with a device for power supply and data transmission as described above and below, and a bicycle with such a sensor bottom bracket.

Further advantages, features and details of the invention will become apparent from the embodiment described below and from the drawing.

Hereinafter, an embodiment of the invention will be illustrated with reference to a figure.

The figure shows a schematic representation of the structure of the device around a shaft.

FIG. 1 shows a schematic representation of the structure of the device 100 around a wave 110 , The wave 110 includes a ferrite 120 , The ferrite 120 is in the figure as a thick circle around the shaft 110 illustrated. The device 100 further includes a secondary coil 115 , For example, a receiving coil, which is also on the shaft 110 is arranged. The secondary coil 115 is shown as a thinner circle next to the ferrite 120 illustrated. The device 100 further comprises a coil carrier 130 concentric around the shaft 110 is arranged and a primary coil 115 , For example, a transmitting coil wears. The primary coil 115 creates a magnetic field in which the secondary coil 115 can rotate. The ferrite 120 aligns the magnetic field. The coil carrier 130 may be in a bottom bracket of a bicycle, for example, the bearing housing. It can also be any other component that is suitable for carrying a coil. Between primary coil 135 and secondary coil 115 is a distance 150 , The distance 150 can arise when the wave 110 is mounted at two bearings, and thus, for example, a spaced area between the shaft 110 and a bearing housing is created. The distance 150 may be a few inches or less than 1 cm. Next are the primary coil 135 and the secondary coil 115 so spaced apart and arranged concentrically around the shaft to each other that signals and energy are transferable. Thus, device is 100 suitable for wirelessly transmitting or exchanging energy or data by means of, for example, the NFC standard.

LIST OF REFERENCE NUMBERS

100

 contraption

110

 wave

115

 secondary coil

120

 ferrite

130

 coil carrier

135

 primary coil

150

 distance

Claims (10)

Contraption ( 100 ) for wireless energy supply and data transmission for a transponder in a rotatable system, comprising: - a shaft ( 110 ), - a coil carrier ( 130 ), which is at a distance from the shaft ( 110 ), - a primary coil ( 135 ), wherein the primary coil ( 135 ) on the coil carrier ( 130 ), and wherein the primary coil ( 135 ) generates a magnetic field, - a secondary coil ( 115 ), the secondary coil ( 115 ) on the shaft ( 110 ), and wherein the secondary coil ( 115 ) is rotatable in the magnetic field, - and wherein the primary coil ( 135 ) and the secondary coil ( 115 ) are spaced apart from each other and concentrically arranged around the shaft to each other that signals and energy are transferable. Device according to claim 1, wherein the device comprises at least one ferrite ( 120 ), and wherein the at least one ferrite ( 120 ) on the secondary coil ( 115 ) and / or on the primary coil ( 135 ), especially between the shaft ( 110 ) and the secondary coil ( 115 ) and / or between the coil carrier ( 130 ) and the primary coil ( 135 ) is arranged. Apparatus according to claim 1 or 2, wherein the primary coil and / or the secondary coil are formed as an annular coil. Device according to one of claims 1 to 3, wherein the primary coil and / or the secondary coil are formed as a planar rectangular coil. Device according to one of claims 1 to 4, wherein the transponder is an RFID tag or an NFC tag. Device according to one of claims 1 to 5, wherein the transponder comprises a data memory. Device according to one of claims 1 to 6, wherein the transponder comprises a processor, in particular a microprocessor or a microcontroller. Device according to one of claims 1 to 7, wherein the transponder comprises a power control unit. A sensor bottom bracket comprising a device for power supply and data transmission according to one of claims 1 to 8. Bicycle with a sensor bottom bracket according to claim 9.

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