JP2001053657A - Non-contact transmitting device and its passive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make transmission power constant regardless of the fluctuation of a transmission distance and also to enable the stable transmission of operation power with a simple circuit configuration by allowing an active module transmitting power to automatically control a power transmission output on the basis of the receiving strength of an information signal received from a passive module. SOLUTION: An active module A transmits power and an information signal including a command control signal from the power transmitting head 4 of a power transmitting part including an oscillation circuit of a frequency for power transmission and transmits the power and the command control signal to a passive module B at a relatively adjacent distance in an non-contact way due to electromagnetic inductive coupling and optical coupling. The module B uses power supplied to a power receiving head 5 as power supply for operation. The module B further transmits a detection signal of signal strength related to the receiving strength of the information signal and receiving power variation as FM waves from a signal transmitting head 11 to the module A. The module A receives the FM waves and performs the output control of an oscillation circuit 1 in accordance with a detection signal extracted by demodulating the FM waves.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention transfers data between a fixed unit and a moving unit which are relatively close to each other and are opposed to each other.
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for transmitting an information signal in a non-contact manner using an electromagnetic wave including an optical region as a medium, and particularly to a device configured as a set of active and passive modules.

That is, the present invention is applied to stationary equipment formed by combining a plurality of sets of apparatuses, automatic machines such as NC machine tools, robots, and transporting apparatuses, and various kinds of moving machines such as vehicles and flying objects. You. Either the fixed side of the main body or the other side that performs movement or movement is equipped with an active module and the other side is equipped with a passive module, and various information such as shape, position, distortion, temperature, color, etc. It transmits signals and power signals in a non-contact manner.

[0003] In this case, fluctuations in power supplied to a circuit related to an information signal in a passive module often have a great effect on the accuracy of information. In such a transmission device, it is suitable for use when it is desired to stably transmit an information signal and electric power in a non-contact manner even with respect to an axis deviation and a distance variation between both modules or a relative high-speed variation. It is something.

[0004]

2. Description of the Related Art Conventionally, there are several communication means based on a wireless communication system.
In the object identification device of 55-117982 and the transmission output control method of Japanese Patent Application Laid-Open No. 56-122246, or the device as seen in Japanese Utility Model Application Laid-Open No. 59-86752, both of the transmission side and the reception side are used. Each is provided with a power supply and transmits and receives information signals.

Further, in the electric power transmission between the fixed and rotating devices disclosed in Japanese Utility Model Application Laid-Open No. 52-34248, the signal transmission device and the data input / output card described in Japanese Utility Model Application Publication No. It is intended for cases where there is not.

[0006]

As a means for stabilizing a transmission apparatus similar to the apparatus of the present invention, an AGC (Automatic Gain) which conventionally adjusts the gain of an amplifier circuit automatically according to the strength of a received signal in a receiving circuit inside a module. Control) circuit is used. However, the AGC in this case often controls the gain of only the receiving circuit portion.

Therefore, as in the apparatus according to the present invention, the power such as the power supply required by the passive module is supplied from the active module in a non-contact manner, and the information such as data transmitted from the passive module is transmitted to the active module in a non-contact manner. In the case of the method of receiving by the transmission method, the transmission loss which increases in proportion to the distance is effective in the round trip.

In such a conventional technique, an active module
If the transmission distance fluctuates even if the distance between the module and the passive module is relatively short, the transmission efficiency fluctuates because the elements related to the tuning of the power transmission circuit and the operating conditions fluctuate in the active module. As a result, the transmission power also changes. Further, in the passive module, fluctuations in transmission power and a reduction in operating power inside the circuit affect various parts of the circuit, causing factors such as malfunction.

Further, for example, when the transmission distance is almost zero, the information receiving circuit of the passive module cannot fully correct the gain only by AGC due to the strong electric field and saturates at the input stage. There is a need for a solution, for example, transmission may not be possible.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an active module and a passive module for transmitting power and information signals in a non-contact manner, and to stabilize transmission power irrespective of fluctuations in transmission distance. In addition, another object of the present invention is to provide a non-contact transmission device for transmitting power and information for stably transmitting operation power with a relatively simple circuit configuration.

[0011]

SUMMARY OF THE INVENTION A non-contact transmission device according to the present invention comprises a fixed-side active module and a mobile-side device provided with an active module and a passive module on the other. The present invention relates to a non-contact transmission device that transmits and receives information in one direction and an information signal to and from each other by using an electromagnetic field or an electromagnetic wave as a medium between a signal transmission head and a signal reception head provided in the system. One of the active modules transmits an information signal including power and a command control signal from a power transmission head of a power transmission unit including an oscillation circuit of a power transmission frequency, and receives a relatively short distance to receive the information signal. Means for non-contact transmission by electromagnetic inductive coupling or optical coupling to the passive module.

The other passive module is a passive-side device comprising the passive module and an accompanying device by performing smoothing rectification processing or the like on the power supplied to the power receiving head of the power receiving unit in a non-contact manner. It is used as a power supply for operation. Further, the detection signal of the signal strength relating to the reception strength of the information signal and the received power change amount that changes according to the fluctuation of the transmission distance between the active module and the power transmission head and the operation state of the circuit received by the power reception head is provided. Means for transmitting an FM wave from the signal transmission head of the signal transmission section to the active module as an FM wave modulated with the output of the oscillation circuit of the signal transmission frequency.

After the FM wave is received by the signal receiving head of the active module, the output of the oscillation circuit of the power transmitting unit is controlled in accordance with the detection signal extracted by the demodulation processing in the signal receiving unit. By providing such means as described above, the configuration is such that the output power of the electric power is made constant.

As described above, according to the present invention, the active module for sending power automatically controls the output of sending power based on the reception strength of the information signal received from the passive module, or the active module for sending power from the active module. After receiving a change in the output of the dispatched power by the passive module, the amount of the change is fed back to the active module to automatically control the dispatch output of the power. In this case, the automatic control range is greatly increased and transmission is stabilized.

The electromagnetic wave used as a medium for transmitting electric power and information signals in a non-contact manner according to the present invention is an alternating current of a commercial frequency or higher and includes a microwave from a low frequency to a microwave. It is applied as a transmission medium.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiments of the present invention described below, power is transmitted from an active module to a passive module, and information signals are transmitted from a passive module to an active module for the sake of simplicity. Although the case where the transmission is performed in a single transmission mode will be described, it goes without saying that the present invention can be applied to a system such as a normal one-way or two-way transmission.

FIG. 1 is a block diagram for explaining an embodiment of an apparatus provided with means for automatically controlling the output and output of electric power based on the signal strength of an information signal from a passive apparatus received by an active module. FIG. In the figure, A is an active module.
And B represent passive modules and active modules.
Module A has a power transmitting unit for handling power and information signals and a signal receiving unit for receiving information signals, and passive module B transmits a power receiving unit for receiving and processing power and information signals and transmitting information signals. It has a signal transmitting and receiving unit and the like.

The power transmitting section of the active module A outputs the output of the f1 oscillation circuit 1 which oscillates the power sending frequency to RF.
The power is amplified by an RF power amplifier 3 received through a (high frequency) buffer amplifier 2 and the electromagnetic wave is radiated from a power transmission head 4 (the configuration of the head will be described later). After this electromagnetic wave is captured by the power receiving head 5 of the passive module B, it becomes a direct current E1 by the rectifying / smoothing circuit 6 and is supplied as a power source for operating each circuit in the passive module B and the additional circuit. The passive device module B operates apparently without power.

In this case, as the distance between the power transmitting head 4 and the power receiving head 5 related to the power transmission increases, the power guided to the power receiving head 5 greatly attenuates.
When installed in a mechanism consisting of a moving part and a fixed part as in the apparatus according to the present invention, generally, it is almost enough if transmission of about several mm (1 to 10 mm) can be stabilized, and it is sufficient if the transmission is within several centimeters. In other words, the transmission efficiency is not extremely reduced. Further, information such as analog data Di1 input from a circuit of a device attached to the passive module or the like is subjected to necessary processing such as scaling by an AF (low frequency) amplifier 7 and then signal transmission. The output from the f2 oscillation circuit 8 for oscillating the frequency for use becomes an FM wave in an FM (frequency modulation) circuit 9, which is amplified in power by an RF power amplifier 10 and radiated as electromagnetic waves from the signal transmission head 11 into the air.

The FM wave is captured by the signal receiving head 12 of the active module A, amplified by the next RF amplifier 13, and then demodulated by the FM detection circuit 14 into information such as original data. AF (low frequency) buffer amplifier 15
After that, the data can be output as information such as output data Do, or the output status can be observed by the display means.

In this case, a part of the output of the RF amplifier 13 is
A voltage control circuit 19 which is detected and converted into a direct current by a carrier detection circuit 16 and is inserted in series with a power supply of the RF buffer amplifier 2 and the RF power amplifier 3 via an appropriate time constant circuit 17 and a variable resistor 18 for gain adjustment. Is applied to the control end. In this manner, the power output can be automatically controlled as described above.

Conventionally, it is needless to say that means for adjusting a bias value of a buffer amplifier or a power amplifier may be applied as a general method for controlling such sending output. Changing these values significantly changes the operation class (A, B, C class, etc.) in the case of a vacuum tube, which is not preferable in terms of efficiency, linearity, and the like. Therefore, in the embodiment of the present invention, the RF output is controlled by automatically adjusting the power supply voltage of the RF buffer amplifier 2 and the RF power amplifier 3 by the voltage control circuit 19 instead of changing the bias value. It is.

In parallel with such a power supply stabilizing means, the signal strength received by the signal receiver of the active module A is always negatively fed back to the power transmitter, ie, when the received signal strength is weak, the output of the power transmitter is output. The circuit is configured to automatically perform a feedback operation to increase the power and to reduce the power in the opposite case, thereby always stabilizing the power reaching the passive module B. In the case where the medium for non-contact power transmission and the information transmission are both electromagnetic waves as in the embodiment of the present invention, the electromagnetic field related to the high-power power transmission system affects the information transmission system. It is also necessary to use different frequencies to avoid this, and to perform filtering and shielding.

As the transmission heads 4 and 11 and the reception heads 5 and 12 for the electromagnetic field, coils each having a capacitor connected in parallel can be used, respectively. The two coils for the signal may be separately used for two pairs as a single turn. However, when the active module and the passive module are used simply facing each other, two types of magnetic cores for power and information signals having different frequency characteristics, each wound with a coil, are integrated. If one head is used for transmission and one is used for transmission and the other is used for reception, only one pair can be used, and the overall shape can be reduced.

In consideration of the transmission efficiency of power or information signals, an air-core coil such as an antenna may be used without using a magnetic core, or a magnetic core may be used for only one of the coils. May be an air-core coil. If the passive module is used by being attached to a rotating shaft or the like, the active module fixed with an air gap outside the passive module may be formed coaxially. Alternatively, for example, if the device on which the passive-side module is installed is a flat plate, a flat head is required. In such a case, printed wiring is used. A single-turn or laminated printed coil can be applied.

Next, FIG. 2 shows that the change in the magnitude of the electric power sent from the active module A is received by the passive module B, and the amount of the change is fed back to the active module A. This embodiment shows an embodiment in which the output power of power is automatically controlled according to the signal strength, and the power transmitted to the passive module B is made constant as a whole.

However, light is used as the transmission medium of the power transmission system,
In this example, an electromagnetic wave is used as a signal transmission medium. The luminous flux for transmitting power radiated from the optical transmission head 20 of the active module A is captured by the optical reception head 21 of the passive module B having an optical / electric conversion function. A part of the output is converted to a DC output E2 by the smoothing circuit 22, and is supplied as an operating power supply for each circuit of the passive module B and the accompanying external circuit.

The other part passes through a time constant circuit 17 having an appropriate time constant and a variable resistor 18 for gain adjustment, and is modulated by the subcarrier 1 oscillation modulation circuit 23 in accordance with the output of the optical reception head 21. Wave Fs1 results. Information such as a data signal Di2 obtained by an external circuit attached to the passive module B is scaled by the AF amplifier 7.
Necessary processing such as ring is performed, and the next subcarrier 2
A modulated wave Fs2 corresponding to information such as the data signal Di2 grown by passing through the oscillation modulation circuit 24 is obtained.

The mixer circuit 25 together with the modulated wave Fs1
, And is further input to the FM circuit 9 driven by the output of the main carrier oscillation circuit 26 to become an FM wave. After being subjected to power amplification in the RF power amplifier 10, the signal is transmitted from the signal transmission head 11 to the space as an information signal of an electromagnetic wave. This signal is received by the signal receiving head 12 of the active module A, then amplified by the RF amplifier 13, and is amplified by the FM detection circuit 14 for the main carrier.
As a result, it is demodulated as a mixed wave of the modulated wave Fs1 'and the modulated wave Fs2' by the subcarrier.

Of these modulated waves, the data signal Fs2 '
Is demodulated by the subcarrier 2 detection circuit 27 and A
It is used in an external circuit as information such as the data output signal Do2 via the F buffer amplifier 15. The modulated wave Fs1 'corresponding to the output of the optical receiving head 21 is demodulated by the subcarrier 1 detection circuit 28, and then passes through the time constant circuit 17 and the variable resistor 18 for gain adjustment. To control the output, it is applied to the control input of a voltage control circuit 19 inserted in series with the power supply circuit.

The output of the AF power amplifier 29 is converted into a light beam from the optical transmission head 20 having an electric / optical conversion function, and emitted to the passive module B. The change in the power transmitted from the active module A is received by the passive module B and returned to the active module A as the signal strength related to the output of the transmitted power. The active module A keeps the signal strength almost constant irrespective of the distance between the modules by applying a negative feedback to the power transmitting section according to the value of the signal strength of the received information signal. be able to. Transmission and reception between the active module A and the passive module B can be performed by various combinations of electromagnetic waves including light, and one head performing optical transmission and electromagnetic reception and the other head performing optical reception and electromagnetic transmission are illustrated. It can be used in other combinations.

(Modification) In the above embodiment, the FM system is used for modulation. However, it is obvious that most of various modulation systems used in ordinary wireless communication and the like can be applied instead. In addition, a normal AGC for only the receiving system in each module may be used together.

The optical transmission head 20 shown in the embodiment of FIG. 2 includes an electric / optical conversion element such as a high-power LED, a semiconductor laser or a gas laser with an optical output modulator, a lens, and the like. Can be used. The optical receiving head 21 includes a phototransistor, a photo diode, a photo-electric conversion element such as a CdS or a photoelectric tube, and an optical element having spectral characteristics such that only light generated by the optical transmitting head is transmitted and a disturbance light is attenuated. An optical system in which a filter is combined can be applied. For these optical systems, a reflecting mirror or the like can be used in addition to the lens.

In the embodiment of the present invention, the change in the reception intensity for automatically controlling the transmission power is extracted from the reception system related to the signal transmission frequency in the active module A. It goes without saying that the extraction can be performed in exactly the same manner even if it is extracted from the reception system related to the transmission frequency or light.

[0035]

According to the present invention, an active module is provided on one of a set of a fixed-side device and a mobile-side device, and a passive module is provided on the other. Power is transmitted from the active module to the passive module. Since signals are transmitted and received between both modules, signals can be transmitted and received while moving the mobile device with respect to the fixed device. Moreover, since the power and the transmission output of the signal are controlled, both can be transmitted and received stably. In addition, since power and signals are transmitted and received using a common head, both can be transmitted only by the electromagnetic coil, and the configuration can be simplified as compared with the case where heads are provided separately for power and signals. Further, by transmitting and receiving power and signals by the optical head, both can be transmitted only by the optical head,
The configuration can be simplified as compared with the case where a head is provided for each power and signal. Then, by combining the signal transmitting and receiving unit with the signal conversion unit, the transmitted signal can be used in various forms. Further, as a passive device including an ancillary device connected to the passive module, by providing a means for outputting from the ancillary device to an external device, and a means for transmitting an information signal converted by the ancillary device,
It is possible to widen the use form of information transmission using the active module and the passive module. Then, modulation using two subcarriers and a main carrier is performed, and furthermore, the information signal is transmitted as an FM wave, so that an information signal can be transmitted with high reliability.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of an apparatus for automatically controlling a power sending output according to the strength of a received signal in an active module according to the present invention.

FIG. 2 shows a change in the output of the transmitted power by a passive module.
FIG. 2 is a block diagram showing an example of an apparatus for automatically controlling a power sending output by feeding back from a module to an active module.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 f1 oscillation circuit 2 RF buffer amplifier 3 RF power amplifier 4 electromagnetic transmission head 5 electromagnetic reception head 6 rectifying and smoothing circuit 7 AF amplifier 8 f2 oscillation circuit 9 FM circuit 10 RF power amplifier 11 electromagnetic transmission head 12 electromagnetic reception head 13 RF Amplifier 14 FM detection circuit 15 AF buffer amplifier 16 Carrier detection circuit 17 Time constant circuit 18 Variable resistor 19 Voltage control circuit 20 Optical transmission head 21 Optical reception head 22 Smoothing circuit 23 Subcarrier 1 oscillation modulation circuit 24 Subcarrier 2 detection circuit 25 Mixer circuit 26 Main carrier oscillation circuit 27 Subcarrier 2 detection circuit 28 Subcarrier 1 detection circuit 29 AF power amplifier A Active module B Passive module

Claims (6)

[Claims] An apparatus comprising a fixed-side device and a mobile-side device, one of these two devices having an active module and the other having a passive module, and transmitting electromagnetic waves for power transmission from the active module to the passive module. In a non-contact transmission device configured to transmit and transmit and receive an information signal transmission electromagnetic wave between the two modules, the active module transmits and receives a power transmission electromagnetic wave and a signal transmission electromagnetic wave. A first head, a power transmission unit that transmits an electromagnetic wave for power transmission via the first head,
A signal transmission / reception unit including a signal transmission / reception head via the first head for transmitting / receiving an electromagnetic wave for transmitting an information signal, and the signal transmission / reception unit forming a control signal relating to power and a signal magnitude received from the passive module; A power control unit that controls each transmission output of the power transmission unit and the signal transmission / reception unit; the passive module includes a second head that transmits and receives a power transmission electromagnetic wave and a signal transmission electromagnetic wave, and the second head. A power receiving unit that receives the electromagnetic wave for power transmission from the active module through the active module, further rectifies and smoothes the power to form power for the power supply, and the power receiving unit that is supplied with power from the power receiving unit via the second head. A signal transmitting / receiving section for transmitting / receiving an information signal including power and a signal receiving state from the active module to / from a signal transmitting / receiving section of the active module; The signal transmission / reception unit transmits an FM-modulated information signal, demodulates the received FM-modulated signal, and provides the demodulated signal to another device. 2. The non-contact transmission device according to claim 1, wherein the first head and the second head are electromagnetic coils. 3. The non-contact transmission device according to claim 1, wherein the first head and the second head are optical heads. 4. The non-contact transmission device according to claim 1, wherein the signal transmission / reception unit has signal conversion means for transmitting / receiving a signal to / from another device. 5. A fixed-side device and a movable-side device, one of these devices having an active module and the other having a passive module, and transmitting electromagnetic waves for power transmission from the active module to the passive module. A passive device used for a non-contact transmission device configured to transmit and transmit and receive an electromagnetic wave for transmitting an information signal between the two modules, wherein an auxiliary device connected to the passive module; An output unit that converts an information signal transmitted from the passive module to the ancillary device into external information in a predetermined form and then outputs the information to the outside of the ancillary device; and converts information input from the outside into an information signal by the ancillary device. Transmission means for modulating the signal into an FM wave signal and transmitting the modulated signal to the active module. Passive device used in the location. 6. A passive device used in a non-contact transmission device according to claim 5, wherein: a subcarrier 1 oscillation modulation circuit for modulating with a received power to form a first modulated wave; Sub-carrier 2 oscillation modulating circuit for forming a second modulated wave, and an FM for modulating a main carrier signal with a mixed signal of the first modulated wave and the second modulated wave to form an FM wave signal
A passive device used for a non-contact transmission device, comprising: a circuit; and a transmitting unit that transmits the FM wave signal to the active module.