Inductive coupler for transferring electrical power

• US 5,656,983 A
• Filed: 04/25/1995
• Issued: 08/12/1997
• Est. Priority Date: 11/11/1992
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Original Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Inventors: Ito, Makoto, Takeuchi, Kazuyoshi, Asahi, Goro
• Primary Examiner(s): Picard, Leo P.
• Assistant Examiner(s): RYAN, STEPHEN
• Application Number:
  US08/428,279
• Time in Patent Office: 840 Days
• Field of Search: 335/210, 335/297, 335/281, 336/83, 336/178, 336/212, 336/233
• US Class Current: 335/297
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: B60L 3/0069 relating to the isolation, e.g. ground fault or leak current
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/34 Plug-like or socket-like devices specially adapted for contactless inductive charging of electric vehicles positioning means for charging devices using inductive energy transfer B60L53/38
• CPC Class Codes: H01F 2003/106 Magnetic circuits using combinations of different magnetic materials
• CPC Class Codes: H01F 2007/1676 Means for avoiding or reducing eddy currents in the magnetic circuit, e.g. radial slots
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

An inductive coupler forming a closed magnetic circuit by mating a primary core assembly having a primary winding and a secondary core assembly having a secondary winding for transferring electrical power from the primary winding to the secondary winding by electromagnetic induction. A thin magnetic protective sheet having high permeability is attached to the mating surfaces of at least one of said primary and secondary core assemblies or placed to be held by the core assemblies. The magnetic sheet can protect the mating surfaces of ferrite cores, if such cores are used, from breakage by absorbing and dispersing the shock of impact caused when the mating surfaces are abutted against each other to close the cores. Provision of a slit or slits in the magnetic protective sheet can reduce eddy currents flowing in the magnetic sheet.

Claims

1. An inductive coupler comprising a primary core assembly having a primary winding, a secondary core assembly having a secondary winding, said primary and secondary core assemblies being matable and separable at the mating surfaces thereof thereof to form a magnetic circuit for transferring electrical power from said primary winding to said secondary winding by electromagnetic induction, and at least one of said primary and secondary core assemblies having attached to its mating surface a thin magnetic sheet of elastomeric material containing magnetic particles.

2. An inductive coupler comprising a primary core assembly having a primary winding, a secondary core assembly having a secondary winding, said primary and secondary core assemblies being matable and separable at the mating surfaces thereof thereby to form a magnetic circuit for transferring electrical power from said primary winding to said secondary winding by electromagnetic induction, and a sheet member having magnetic portions and nonmagnetic portions formed integrally with said magnetic portions, said sheet member being placed with said magnetic and nonmagnetic portions thereof held between said mating surfaces of said primary and secondary core assemblies in the mated position thereof, and said nonmagnetic portions being made of an elastomeric material.

3. An inductive coupler according to claim 2, wherein said magnetic portions of said sheet member are made of an elastomeric material containing therein magnetic particles.

4. An inductive coupler comprising a primary core assembly having a primary winding, a secondary core assembly having a secondary winding, said primary and secondary core assemblies being matable and separable at the mating surfaces thereof thereby to form a magnetic circuit for transferring electrical power from said primary winding to said secondary winding by electromagnetic induction, and a sheet member having a magnetic portion and a nonmagnetic portion formed integrally with said magnetic portion, said nonmagnetic portion of said sheet member projecting slightly further than the surface of said magnetic portion of the sheet member with the sheet member formed such that a clearance is provided between said magnetic and nonmagnetic portions, said sheet member being placed with said magnetic portion thereof held between said mating surfaces of said primary and said secondary core assemblies in the mated position thereof.

5. An inductive coupler comprising a primary core assembly having a primary magnetic core structure including a plurality of primary pole faces and a primary winding, a secondary core assembly having a secondary magnetic core structure including a plurality of secondary pole faces and a secondary winding, said primary and secondary core assemblies being matable and separable at mating surfaces thereof, pole face to pole face, thereby to form a magnetic circuit for transferring electrical power from said primary winding to said secondary winding by electromagnetic induction, and a thin layer of elastomeric material covering all of the pole faces and intervening areas of the mating surfaces of at least one of said primary and secondary core assemblies, said layer being at least coextensive with the interface between said mating surfaces when said assemblies are mated.

6. An inductive coupler according to claim 5, wherein at least a major portion of said elastomeric material that covers said pole faces contains magnetic particles while the portions of said elastomeric material that cover said intervening areas are essentially nonmagnetic.