Abstract: An electromagnetic coupling apparatus includes a ring case, a coil and a connector. The ring case has an annular groove. The coil is an electrical wire and is disposed in the annular groove of the ring case. An opening is formed through the ring case in its closed end surface. The connector is disposed on the closed end surface of the ring case and covers the opening. Each of a first end and a second end of the coil are connected to one of a pair of lead wires, respectively, of an electric circuit via one of a pair of contacts, respectively in the connector. The connector has a housing supporting the first and the second ends of the coil and the contacts and a cap closing an end opening of the housing. The coil is covered substantially by an annular resin case, and the housing is formed integrally with the annular resin case.

Abstract: An electromagnetic coupling apparatus includes a ring case, a coil and a connector. The ring case has an annular groove. The coil is an electrical wire and is disposed in the annular groove of the ring case. An opening is formed through the ring case in its closed end surface. The connector is disposed on the closed end surface of the ring case and covers the opening. Each of a first end and a second end of the coil are connected to one of a pair of lead wires, respectively, of an electric circuit via one of a pair of contacts, respectively in the connector. The connector has a housing supporting the first and the second ends of the coil and the contacts and a cap closing an end opening of the housing. The coil is covered substantially by an annular resin case, and the housing is formed integrally with the annular resin case.