Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
  • B60R16/00—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for
  • B60R16/02—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements
  • B60R16/023—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements for transmission of signals between vehicle parts or subsystems
  • B60R16/027—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements for transmission of signals between vehicle parts or subsystems between relatively movable parts of the vehicle, e.g. between steering wheel and column
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
  • H04B5/20—Near-field transmission systems, e.g. inductive or capacitive transmission systems characterised by the transmission technique; characterised by the transmission medium
  • H04B5/24—Inductive coupling
  • H04B5/26—Inductive coupling using coils
  • H04B5/266—One coil at each side, e.g. with primary and secondary coils
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
  • H01F38/14—Inductive couplings
  • H01F2038/143—Inductive couplings for signals
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
  • H01F38/18—Rotary transformers
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
  • H04B5/20—Near-field transmission systems, e.g. inductive or capacitive transmission systems characterised by the transmission technique; characterised by the transmission medium
  • H04B5/24—Inductive coupling
  • H04B5/26—Inductive coupling using coils
  • H04B5/263—Multiple coils at either side

Definitions

• the invention relates to contactless rotary transformer.
• Rotary transducers serve to transmit electrical signals between parts that rotate relative to one another.
• rotary joints There are several different rotary joints known.
• contact slip rings in which metal or carbon brushes run on mostly metallic tracks, are used for galvanic transmission.
• Contactless rotary joints are based on the principle of inductive or capacitive coupling. These rotary joints are almost free of wear compared to the contacting slip rings, since a mechanical contact between the two rotatable parts is not necessary. Due to the physical separation of the two rotatable parts, such rotary transformers can also be encapsulated excellently against environmental influences.
• a disadvantage of non-contact rotary encoders is compared to mechanical slip rings usually much higher cost.
• a contactless rotary transformer for the steering wheel of a motor vehicle is disclosed. Beard.
• a clock signal modulated on a carrier is transmitted from the motor vehicle to the steering wheel.
• a damping of the loop antennas takes place by means of an impulse switch integrated in the steering wheel. This can be detected on the part of the motor vehicle by a corresponding decrease in the signal amplitude.
• the power supply of the electronics in the steering wheel takes place by means of a separate galvanic rotary transformer. If such an energy supply were also realized without contact, additional components would be necessary.
• the object of the invention is to make a comparison with the prior art further simplified system for querying system states such as switch positions between a fixed and a rotating part, which can be dispensed with an additional energy supply of the components of the rotating part.
• a device for non-contact interrogation of system states of a rotatable part 20, which is rotatable relative to a fixed part 10, is based on inductive coupling.
• the fixed part 10 comprises a first coil 11, which from a Signal generator 12 is fed.
• Magnetically coupled to the first coil 11 is a second coil 21, which is arranged on the rotatable part 20.
• the coils may optionally be realized as simple conductor loop, as coils with bifilar windings, which form a localized field due to antiparallel currents, as air coils or as coils with iron or ferrite cores. Likewise, combinations of different coil types are possible. What is essential here is the magnetic coupling of the first coil 11 with the second coil 21.
• the second coil 21 is supplemented by means of at least one capacitor 22 to form a resonant circuit.
• This at least one capacitor 22 may be designed as a discrete component. However, it can also be a parasitic capacitance of the arrangement.
• at least one switching element (23a, 23b) is provided which switches at least one further impedance (24a, 24b) to this resonant circuit.
• the wiring can be done here either in series or in parallel.
• a switching element may be, for example, a semiconductor switch or a mechanical contact.
• impedance here refers to an electronic component which has a real and / or imaginary impedance. This can be, for example, an inductance, a capacitance or even a resistor.
• a signal generator 12 which is assigned to the fixed part 10, is changed in its frequency until at least one resonance frequency of the arrangement has been reached.
• This can be a series resonance or a parallel resonance.
• the control of the signal generator by means of an evaluation device 13, which further comprises means for detecting a resonant frequency.
• These can be, for example, means for measuring the current amplitude, the voltage amplitude, the time characteristic of the current, its temporal voltage curve or else the impedance.
• a current, a voltage and / or an impedance of the resonant circuit can be determined in addition to the frequency to determine a resonant frequency. From the frequency or another electrical variable can now be deduced on the respective activated electricalmaschine- element (23a, 23b).
• a further resonant capacitance is connected in parallel to the at least one capacitance 22 by a switching element, then the resonant frequency of the parallel resonant circuit is reduced accordingly.
• the value of the capacitance can now be determined from the new resonance frequency and thus returned to the switching element activated for this purpose. be concluded.
• a table could be provided in the evaluation device in which the direct relationship between a resonance frequency and the switching element activated for this purpose is included.
• a corresponding evaluation is likewise to be carried out in the case of a parallel connection of an inductance or also in the case of a further series connection of an inductor or a capacitor to the at least one capacitor 22.
• a further device comprises, instead of the previously described controllable signal generator 12, a freely oscillating signal generator whose frequency is determined by the resonant circuit. If a further, preferably imaginary impedance is now connected to the resonant circuit by at least one switching element, the resonance frequency of the resonant circuit and thus also the operating frequency of the signal generator changes accordingly.
• An evaluation can be carried out by the evaluation device 13 as described above.
• a signal generator 12 is provided, which can be varied within a predetermined frequency range, controlled by the evaluation device in its operating frequency.
• the evaluation device has means for measuring at least one electrical parameter such as frequency, amplitude, phase at the first coil.
• This measurement is carried out on directly at the first coil, but also indirectly, for example decoupled by other electronic components.
• a conclusion to the respective activated switching element is also possible. For example, at a certain, preferably at several frequencies, an attenuation or even an impedance, preferably in terms of magnitude and phase, can be determined.
• an attenuation or even an impedance preferably in terms of magnitude and phase.
• a further device has a signal generator 12, which is controlled by an evaluation device 13 such that it outputs signals of several frequencies.
• the evaluation device 13 is designed such that it at least one, but preferably several different due to the measurement of at least one electrical parameter such as frequency, amplitude, phase at the first coil Recognize resonance frequencies and can conclude from this to the activated switching elements.
• the signals output by the signal generator 12 may be, for example, pulses, preferably short pulses, broadband noise or else multi-frequency signals which have frequency components at the possible resonance frequencies of the arrangement.
• the evaluation is now preferably frequency-selective, for example by filtering with discrete filters or a Fourier transformation. By such a configuration, different switching states can be detected in a short time or simultaneously.
• At least one means for plausibility control is provided. This may be part of the evaluation device 13, for example.
• the results of measurements made are compared with specified target values. If, for example, in the case of two switching elements, a total of four resonance frequencies of the arrangement are possible, they can be compared with predetermined setpoint frequencies. If the actually determined resonant frequencies are within a permissible tolerance field around the reference frequencies, then a valid measuring signal can be signaled. But if these are outside a permissible tolerance field, an error in the measurement can be signaled.
• Activation or deactivation of a switching element or even more switching elements take place simultaneously. If several switching elements are activated simultaneously, several bits of information can be transmitted simultaneously.
• auxiliary power for supplying electronic components on the side of the rotatable part 20 can be additionally coupled out of the second coil 21.
• the actual coding and transmission of information according to the invention takes place without such a coupling additional auxiliary power.
• a first impedance with a reference channel comprising a further first coil 11 fed by a further first signal generator 12 and a further second coil 21 coupled thereto can be measured and connected by a switch to the actual measuring channel.
• a further embodiment of a device according to the invention consists in that optionally the first coil 11 and / or the second coil 21 comprises a plurality of partial coils. These partial coils are also magnetically coupled together.
• a first partial coil of the first coil 11 can be fed by the signal generator 12, while a second partial coil of the first coil 11 is used by the evaluation device 13.
• 21 different impedances can be switched by means of switching elements at different sub-coils of the second coil.
• the various sub-coils do not have to be mechanically rigidly connected to one another, but can be movable relative to one another. Thus, the system states of various parts that are moving at different speeds, or at different positions can be queried.
• An inventive method for the non-contact query of system states of a relative to a fixed part (10) rotatable member (20) wherein the fixed part (10) a first coil (11) fed by a signal generator (12) and the rotatable member (20) has a second Coil (21) which is magnetically coupled to the first coil (11) comprises the following steps:
• Fig. 1 shows in a general form schematically a device for non-contact query system states.
• FIG. 2 shows a variant of the invention with a plurality of switching elements and a plurality of further impedances as capacitances.
• FIG. 3 shows a further embodiment of the invention with series-connected impedances as inductances.
• Fig. 4 shows a further embodiment of the invention with a tunable capacitance.
• Fig. 5 shows another embodiment with a resonant circuit as impedance.
• FIG. 1 shows schematically in general form a device according to the invention.
• a first coil 11 which is fed by a signal generator 12, and an evaluation device 13.
• the rotatable part 20, which is rotatable relative to the fixed part 10 a second coil 21 having at least one capacitor 22 and a switching element 23, which can turn on an impedance 24 to the resonant circuit assigned.
• the two coils 11 and 21 are magnetically coupled together. This results in the example shown here alone by the close spatial arrangement. To improve the coupling can be used in addition to coils of several turns optionally also ferrite or iron materials.
• switching element 23 When switching element 23 is open, the additional impedance 24 is decoupled from the resonant circuit.
• the resonance frequency is determined by the second coil 21 and the capacitance 22.
• the impedance 24 is connected in parallel with the second coil 21 and the capacitor 22. If this impedance 24 is, for example, a capacitance, then the resonant frequency decreases correspondingly due to the higher total capacitance of the parallel resonant circuit.
• FIG. 2 shows a variant of the invention with a plurality of switching elements and a plurality of further impedances as capacitances.
• a capacitance 22 is again connected in parallel here as well.
• a first series circuit of a first switching element 23a and a first impedance 24a in the form of a capacitance and a second switching element 23b and a second impedance 24b are also connected in parallel in the form of a capacitance.
• the resonance frequency can be further reduced. Suitable dimensioning of the capacitances results in characteristic resonance frequencies with each combination of switch positions.
• the capacitance 24a is twice as large as the capacitance 22 and the capacitance 24b four times greater than the capacitance 22. If inductances were used instead of capacitances in this example, the resonant circuit inductance would be reduced by parallel connection in the case of closed circuit elements and increase the resonant frequency accordingly. It is also possible to combine inductors and capacitors. For example, an inductance could be connected in series with the switching element 23a instead of the indicated capacitance 24a. This would be closed when
• FIG. 3 shows a further embodiment of the invention with series-connected impedances as inductances.
• inductances 24a and 24b could also be permanently connected in series between the second coil 21 and the capacitor 22, in which case the inductance 24a is bridged by a switching element 23a connected in parallel therewith and the inductance 24b by a switching element 24b connected in parallel therewith , Furthermore, inductances and capacitances could be combined with each other. Likewise, instead of an inductance as an impedance, a resonant structure such as a resonant circuit can be switched. This may have an optional damping in the form of a resistor.
• FIG. 4 shows a further embodiment of the invention with a tunable capacitance.
• a tunable capacitance may be a capacitance diode, a capacitor value set by a mechanical system condition (for example, the plate spacing of a plate capacitor), or a variable capacitor driven by a motor.
• This tunable capacitance is controlled by a control unit 25.
• a controller may be, for example, according to the measurement signal of a sensor.
• a tunable inductance or else a variable resistor can also be realized.
• lossy magnetic cores can be used, for example, change the losses of an inductor with variable core position.
• Figure 5 shows another embodiment of the invention with a resonant circuit as impedance.
• the arrangement corresponds largely to the arrangement of Figure 2.
• a resonant circuit consisting of a series circuit of an inductance and a capacity for the impedance 24b is provided. Again, as described above, the resonant frequency of the device can be determined. From this it is possible to conclude again on the capacitance or inductance.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Electronic Switches (AREA)
• Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
• Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
• Arrangements For Transmission Of Measured Signals (AREA)
• Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
• Filters And Equalizers (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Related Child Applications (1)

Publications (1)

Family

ID=37609188

Family Applications (1)

Country Status (5)

Cited By (4)

Families Citing this family (5)

Citations (5)

Family Cites Families (8)

• 2006
  • 2006-11-07 CN CN200680049070XA patent/CN101365610B/zh active Active
  • 2006-11-07 JP JP2008539320A patent/JP2009515447A/ja active Pending
  • 2006-11-07 EP EP06818392A patent/EP1948479B1/de active Active
  • 2006-11-07 WO PCT/EP2006/010633 patent/WO2007054259A1/de not_active Ceased
• 2008
  • 2008-05-06 US US12/115,631 patent/US20080252336A1/en not_active Abandoned

Patent Citations (5)

Also Published As

Similar Documents

Legal Events