Contactless power distribution system

• US 5,831,841 A
• Filed: 07/28/1997
• Issued: 11/03/1998
• Est. Priority Date: 08/02/1996
• Status: Expired due to Term

• Current Assignee: Daifuku Company Limited
• Original Assignee: Diafuku Company Limited
• Inventors: Nishino, Shuzo
• Primary Examiner(s): Riley, Shawn
• Application Number:
  US08/901,726
• Time in Patent Office: 463 Days
• Field of Search: 363/37, 191/10, 307/10.1, 318/16, 336/119, 336/178
• US Class Current: 363/37
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields

Abstract

A primary inductive path to which a high-frequency current is supplied from a power supply is laid along a guide rail for carrying car bodies and secondary electric power receiving circuit for receiving electric power from the primary inductive path in a contactless mode are disposed in the car bodies. Inductance in the primary inductive path is adjusted by disposing, in the power supply, a dummy inductor which is composed by overlapping a plurality of planar ferrite cores with gaps reserved so as to form a plurality of ferrite blocks and combining these ferrite blocks so as to form at centers thereof a run-through slot for passing the primary inductive path. Further, the secondary electric power receiving circuit is composed of a pick-up coil in which an electromotive force is generate by a magnetic flux produced by the primary inductive path, a capacitor which composes, together with the pick-up coil, a resonant circuit resonating with a frequency in the primary inductive path, a rectifier circuit connected to the capacitor, and a constant-voltage control circuit which is connected to the rectifier circuit and controls an output voltage to a standard voltage, and uses standard voltage generators which set the standard voltage of the constant-voltage control circuit at two steps in proportion to a load electric power as well as a controller for switching the standard voltage generators.

Claims

1. A contactless power distribution system comprising a

primary inductive path which is laid along a moving path for moving bodies and passes a high-frequency current, and

secondary electric power receiving circuits which are disposed in said moving bodies and receive electric power from said primary inductive path in a contactless mode,

characterized in that

said contactless power distribution system uses an inductor for adjusting inductance in said primary inductive path, and

said inductor is composed by overlapping a plurality of planar ferrite cores while reserving gaps so as to form a plurality of ferrite blocks and combining these ferrite blocks so as to form at centers thereof a run-through slot for passing said primary inductive path.

2. A contactless power distribution system according to claim 1 wherein

said ferrite blocks of the inductor are configured to permit optionally changing a number of gaps reserved between the ferrite cores.

3. A contactless power distribution system according to claim 1 wherein

said ferrite blocks of the inductor are molded with resin.

4. A contactless power distribution system according to claim 1 wherein

said ferrite cores of the inductor are accommodated in a frame body and said frame body is configured to maintain the gaps between said ferrite cores.

5. A contactless power distribution system comprising a

primary inductive path which is laid along a moving path for moving bodies and passes a high-frequency current, and

secondary electric power receiving circuits which are disposed in said moving bodies and receive electric power from said primary inductive path in a contactless mode,

characterized in that

said secondary electric power receiving circuit is composed of a coil disposed in opposition to said primary inductive path, a capacitor which is connected to said coil and composes, together with said coil, a resonant circuit resonating with a frequency in said primary inductive path, a rectifier circuit connected to said capacitor, and a constant-voltage control circuit which is connected to said rectifier circuit, controls an output voltage to a standard voltage and supplies it to a load, and

said contactless power distribution system includes setting means which sets the standard voltage of said constant-voltage control circuit stepwise in proportion to an electric power for said load.

6. A contactless power distribution system according to claim 5 wherein

said setting means sets the standard voltage at two steps by judging a load electric power in use for the load.