Inductive coupler for transferring electrical power

• US 5,379,021 A
• Filed: 12/09/1993
• Issued: 01/03/1995
• Est. Priority Date: 12/11/1992
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Original Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
• Inventors: Ito, Makoto, Asahi, Goro, Kashiwagi, Yoichiro
• Primary Examiner(s): Kozma, Thomas J.
• Application Number:
  US08/164,421
• Time in Patent Office: 390 Days
• Field of Search: 336/83, 336/90, 336/92, 336/DIG. 2, 336/212, 336/66, 336/210, 320/2
• US Class Current: 336/83
• 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 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
• CPC Class Codes: Y10S 336/02 Separable

Abstract

An inductive coupler for transferring electrical power from the primary to the secondary is disclosed. A secondary coil assembly having a pair of cores each having a secondary winding is disposed in a case having an opening at one end thereof. The core has a central post projecting from the axial center of a disc-shaped base and an annular skirt projecting from the rim of the base in the same direction, thus forming therebetween an annular groove in which the secondary winding is disposed. As a coil case having a primary winding is inserted between the paired cores and moved further inward of the case, the secondary coil assembly is moved inward of the case. During this movement of the secondary coil assembly, its paired cores are caused to displace toward each other while being guided by pins sliding along guide slits until the cores are mated together thereby to form a magnetic circuit of the inductive coupler. Provisions are also made to retain the secondary coil assembly in the position where the cores are closed and also to urge the secondary coil assembly toward the opening of the case.

Claims

1. An inductive coupler comprising:

a first coil assembly having a pair of cores and a first winding disposed in at least one of said cores;

a case housing therein said first coil assembly and having an opening at one end thereof, said first coil assembly being movable toward and away from said opening and said cores being movable toward and away from each other in said case;

a second coil assembly having a second winding and insertable between said cores of the first coil assembly through said opening of the case;

guide means for causing said cores of the first coil assembly to move toward each other as said second coil assembly inserted between the cores is moved to push the first coil assembly in the case until a magnetic circuit of said inductive coupler is formed.

2. An inductive coupler according to claim 1, wherein said second coil assembly includes a coil case supporting said second winding, said coil case being adapted to be insertable between said cores through said opening and to cause said first coil assembly to move in said case away from said opening thereof.

3. An inductive coupler according to claim 2, further comprising means for guiding said coil case when the coil case is being inserted between said cores and also locating the coil case with respect to said first coil assembly when the coil case has been inserted between the cores.

6. An inductive coupler according to claim 1, wherein each of said cores has a central post projecting inward from the axial center of a core base and an annular skirt projecting inward from the rim of said base and forming with said center post an annular groove in which said first winding is disposed, and said coil case has a core piece in the region encircled by said second winding, said magnetic circuit being formed with said paired cores mated together with the opposite surfaces of said core piece of the coil case.

7. An inductive coupler according to claim 6, said guide means being operable to move said paired cores toward each other such that said paired cores are mated together with the opposite surfaces of said core piece of the coil case.

9. An inductive coupler according to claim 1, wherein said first coil assembly provides the primary and said second coil assembly provides the secondary of said inductive coupler, respectively.

10. An inductive coupler according to claim 1, wherein said first coil assembly provides the secondary and said second coil assembly provides the primary of said inductive coupler, respectively.

11. An inductive coupler according to claim 1, further comprising a cover adapted to open and close said opening of the case and means for holding said cover in its closed position.

12. An inductive coupler according to claim 6, further comprising means for releasably retaining said first coil assembly in the state where said magnetic circuit is formed, and means for urging said first coil assembly toward said opening of the case.

4. An inductive coupler according to claim is wherein each of said cores has a central post projecting inward from the axial center of a core base and an annular skirt projecting inward from the rim of said base and forming with said center post an annular groove in which said first winding is disposed, and said coil case has an opening defined by said second winding for receiving therein said central posts of the cores, said magnetic circuit being formed with said paired cored mated together at said center posts and peripheral skirts thereof.

5. An inductive coupler according to claim 4, said guide means being operable to move said paired cores toward each other such that said center posts of the cores are inserted and fitted in said opening of the coil case.

8. An inductive coupler according to claim 4, further comprising means for releasably retaining said first coil assembly in the state where said magnetic circuit is formed, and means for urging said first coil assembly toward said opening of the case.