Pipe joint construction

A pipe joint construction comprising an elastic seal member for hermetically sealing between an inner circumferential surface of a receiving pipe section and an outer circumferential surface of an inserted pipe section inserted into and connected to the receiving pipe section in a pipe axis direction, and a lock member provided interior to the inner circumferential surface of the receiving pipe section adjacent a receiving opening thereof for preventing separating movement of the pipe sections by contacting an engaging projection protruding from the outer circumferential surface of the inserted pipe section in the pipe axis direction,

• wherein the construction further comprises an attachment/detachment control device for attaching and detaching the lock member to/from the receiving pipe section by rotating the lock member about the pipe axis direction relative to a rotating operation passage of a rotating operation guide groove formed in an inner circumferential surface of the receiving opening of the receiving pipe section and by moving, in the pipe axis direction, the lock member placed in a specific attachment/detachment operating position in a passage of rotation,
• the attachment/detachment control device includes a plurality of circumferentially divided control members insertable and removable in the pipe axis direction through a space between the outer circumferential surface of the inserted pipe section and the inner circumferential surface of the receiving pipe section, and a plurality of circumferentially extending split lock pieces forming the lock member and dispersedly formed on the control members, and the receiving pipe section includes, formed adjacent a receiving opening end thereof, attachment/detachment recesses for allowing insertion and removal of the split lock pieces in the pipe axis direction, and retainer wall portions for contacting the split lock pieces in the pipe axis direction when the split lock pieces inserted through the attachment/detachment recesses are rotated about the pipe axis direction to a predetermined attachment position thereby to prevent disengaging movement of the lock pieces,
• the pipe joint construction further comprises a return preventive device provided for receiving the split lock pieces in positions advanced on a removing side in the pipe axis direction in the rotating operation passage when the split lock pieces inserted into the receiving pipe section are rotated along the rotating operation passage, and for preventing or restraining a relative rotation of the split lock pieces in a receiving position toward the specific attachment/detachment operating position, and
• the pipe joint construction further comprises an elastic urging element provided between the split lock pieces and the receiving pipe section in the rotating operation passage, and provided for urging the split lock pieces to the receiving position of the return preventive device while being brought into contact with the split lock pieces and the receiving pipe section in the pipe axis direction.