Signal transmission device

• US 4,837,556 A
• Filed: 08/30/1988
• Issued: 06/06/1989
• Est. Priority Date: 04/15/1985
• Status: Expired due to Term

• Current Assignee: Kabuskiki Kaisha Nihon System Kenkyusho
• Original Assignee: Kabushiki Kaisha Nihon Denzai Kogyo Kenkyusho
• Inventors: Matsushita, Akira, Nakano, Shohkichi
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US07/239,043
• Time in Patent Office: 280 Days
• Field of Search: 340/310 R, 340/310 A, 340/539, 340/531, 455/52, 455/69, 455/127, 455/600-603, 455/605, 455/606
• US Class Current: 369/47.1
• CPC Class Codes: B64G 1/428 Power distribution and management
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: H01F 2038/143 for signals
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H01F 38/18 Rotary transformers
• CPC Class Codes: H04B 14/00 Transmission systems not characterised by the medium used for transmission details thereof H04B1/00

Abstract

A device adapted to transmit a signal and a power with an electromagnetic wave or light being as the transmission medium. This device comprises active and passive modules each provided with means for effecting transmission and reception of at least one of the electromagnetic wave or light, and a signal processing circuit. Each module may further comprise an output or frequency control circuit. One of these modules is provided at a moving body such as a rotary body, and the other is provided at a fixed body to effect both signal transmission and power transmission between the moving and fixed sides.

Claims

1. A signal transmission device for controlling and providing power to a load, said device comprising an active module and a passive module, one of said modules having means for generating a repetitive electrical signal and one of said modules having means for frequency modulating the repetitive signal to provide modulated signals,

said active module including means for transmitting modulated electromagnetic signals based upon the modulated signals, the modulated electromagnetic signals including light signals, and means for receiving modulated electromagnetic signals, including light signals;

a passive module physically remote from and in electromagnetic transmissive communication with said active module, said passive module having electronic circuitry including means for transmitting modulated electromagnetic signals, based upon the modulated signals, to said active module, means for receiving the modulated electromagnetic signals transmitted from said active module, and means for deriving power from the modulated electromagnetic signals received from said active module for supplying power to said electronic circuitry and an electrical load connected to said passive module.

2. A signal transmission device as set forth in claim 1, wherein each module comprises at least one pair of electromagnetic heads, each said electromagnetic head comprising a plurality of magnetic cores having different frequency characteristics and transmitting and receiving coils provided at said magnetic cores, the heads of each pair of electromagnetic heads being disposed opposite to each other.

3. A signal transmission device as set forth in claim 1, wherein said active module comprises a transmitting head and said passive module comprises a receiving head for transmitting and receiving power, said heads being separated by a magnetic fluid.

4. A signal transmission device as set forth in claim 1, wherein said transmitting means of said active module comprises a transmitting head for transmitting power and said receiving means of said passive module comprises a receiving head for receiving transmitted power, each of said heads including a planar coil.

5. A signal transmission device as set forth in claim 1, further comprising charge storage means provided with said passive module, said charge storage means adapted to be charged by power transmitted from said active module by the modulated electromagnetic signals, whereby said storage means becomes operative as a power source.

6. A signal transmission device as set forth in claim 1, wherein the modulated electromagnetic signal has a frequency providing a clock source common to said modules.

7. A signal transmission device as set forth in claim 1, wherein said modulated electromagnetic signals transmitted by said transmitting means of said passive module comprises an information signal, said active module further comprising means responsive to the information signal to automatically control transmission output of power for said passive module from said active module according to the signal intensity of the information signal to achieve optimal power transmission.

8. A signal transmission device as set forth in claim 1, wherein said passive module further comprises feedback means for providing to said active module a feedback signal indicative of a change in power output, and said active module further comprising means for automatically controlling transmission output of power in response to a received feedback signal to achieve optimal power transmission.

10. A signal transmission device as set forth in claim 1, wherein said active and passive modules include means for detecting a change in a transmission parameter in a transmission therefrom and for automatically controlling the transmission frequency of said transmission to place the transmission in an optimum condition.

11. A signal transmission device as set forth in claim 1, wherein one of said modules further comprises means for generating a transmission command signal and the other of said modules includes means for sampling and accumulating data in a data storage unit, said one module transmitting the accumulated data to the other module in response to the transmission command signal.

12. A signal transmission device as set forth in claim 11, wherein said transmission command signal is transmitted on the basis of the signal intensity of a data signal transmitted from said passive module to said active module.

13. A signal transmission device as set forth in claim 1, wherein said passive module further comprises charge storage means chargeable by received power, said device further comprising a circuit for determining a charged condition of said storage means and means for causing transmission of a data signal from said passive module to said active module at a predetermined time with said charge storage means acting as a power source.

14. A signal transmission device as set forth in claim 13, wherein said transmitting means of said active and said passive modules are opposite to each other, said device further comprising a timer circuit for timing the charging of said charge storage means.

15. A signal transmission device as set forth in claim 1, wherein at least one of said modules further comprises a detector circuit for detecting whether said transmitting means of said active and passive modules are opposite to each other, and control means responsive to a detection signal from said detector circuit indictative of the relative positions of said modules for controlling the charging of said storage means.

16. A signal transmission device as set forth in claim 1, wherein each of said modules comprises information processing means.

17. A signal transmission device as claimed in claim 6, wherein the modulated electromagnetic signal is a light signal.

18. A signal transmission device as claimed in claim 1, wherein:

said device further comprises a plurality of said passive modules, each passive module arranged on a corresponding sheet also having printed matter thereon, and means fastening the plurality of sheets together to form a book;

said transmitting means and said receiving means of said active and passive modules comprise transmitting and receiving heads, the modulated electromagnetic signals transmitted by said transmitting heads including a power signal and an information signal;

said electronic circuitry of each of said passive modules further comprises an information processing circuit, a memory, an information holding circuit, a page decision circuit, and a signal controller connecting said page decision circuit to said information processing circuit,

said active module comprises driving means connected to said transmitting means and said receiving means, said driving means having said repetitive signal generating means in the form of an oscillator, signal input means, and data processing means, including information reading and writing means, connecting said signal input means to said transmitting means,

said device further comprises reproducing means connected to said driving means for reproducing the content of said sheets.

19. A signal transmission device as set forth in claim 1, wherein said frequency modulating means comprises a frequency shift modulator.

9. A signal transmission device as set forth in claim -, wherein said active and passive modules include means responsive to a change in transmission parameters depending on the distance between said passive and active modules or an environmental condition for generating a signal representative of the change and transmitting the generated signal to the other of said modules, said other module including means for automatically controlling the transmission frequency in response to the signal representative of the change to place the transmission in an optimum condition.