Attachment structure of connector

An attachment structure of a connector, the connector comprising an internal fitting body and an external fitting body that are fitted to each other, so that a plug in either the internal fitting body or the external fitting body and a socket in the other are connected to each other in a manner that prevents detachment of the fixed connector in a fitting direction,

• a key groove which extends in an axial direction of a cylinder on an inner circumferential surface, external retainer insertion grooves which are formed at an inner circumferential portion on both sides of the key groove with the key groove interposed therebetween, and a retainer insertion inlet which communicates with the external retainer insertion grooves are formed in the external fitting body,
• the internal fitting body including a pressing projection which is provided to be protruded on an outer circumferential surface and is inserted into the key groove, and an internal retainer insertion groove which is formed at an outer circumferential portion on both sides of the pressing projection with the pressing projection interposed therebetween is formed in the internal fitting body, wherein
• a retainer in which paired insertion pieces are supported on both ends of a retainer base portion is inserted from the retainer insertion inlet, the insertion pieces are inserted across the internal retainer insertion groove and the external retainer insertion grooves, and the retainer base portion is overlapped between edge portions on both sides of the pressing projection and on both sides of the key groove.