Patent ID: 8749335

Claim:
A reactor comprising: a reactor core in which two U-shaped core members, each of which is integrally formed by a magnetic material, are connected in a ring shape with gap sections including adhesive layers therebetween; a primary insert-molded resin part which is provided covering at least outer periphery surfaces of leg parts of the core member other than adhesion surfaces of the core members and which includes joint sections formed around end surfaces of the leg parts which form the adhesion surfaces; a coil which is placed around the gap sections and the leg part of the core member; and a secondary insert-molded resin part which is made of a thermoplastic resin and which is insert-molded around the coil to fix the coil on the reactor core and fix the leg parts of the two core members in a connected state, wherein the joint sections of the primary insert-molded resin parts are fitted to each other in a state where the core members are placed connected in a ring shape, to form a peripheral wall surrounding the gap section, and the peripheral wall is formed by a frame shaped inner recess formed on one of the two joint sections, and a frame shaped projection formed on the other joint section, being fitted to each other, and wherein a gap for venting air from the gap section is formed between the inner recess and the projection which are recess-projection fitted to each other, and a size of the gap is set to a size which allows discharge of the air from the gap section, but prevents easy intrusion of melted thermoplastic resin for the second insert-molded resin part.