Air intake apparatus and manufacturing method of air intake apparatus

A manufacturing method of an air intake apparatus, comprising:

• a step of attaching a valve body to a first member, the valve body rotating between an open position and a closed position to open and close a fluid passage formed at a partition wall dividing an inside of a surge tank for an internal combustion engine into two parts, the valve body being out of contact with the partition wall at the open position and being in contact with the partition wall at the closed position;
• a step of forming an air intake apparatus body including the surge tank for the internal combustion engine in a manner that the first member to which the valve body is attached and a second member are joined to each other by vibration welding;
• and
• the step of forming the air intake apparatus body including a step of joining the first member and the second member to each other by the vibration welding in a state where a jig-receiving portion arranged in a vicinity of the fluid passage of the first member is held by a jig, wherein
• the first member includes an actuator attach portion to which an actuator rotating the valve body is configured to be attached,
• the jig-receiving portion is provided at the actuator attach portion,
• the step of forming the air intake apparatus body includes a step of joining the first member and the second member to each other by the vibration welding in a state where the jig-receiving portion of the actuator attach portion is held by the jig,
• the first member corresponds to a middle piece including the partition wall dividing the inside of the surge tank into the two parts,
• the second member corresponds to an upper piece arranged at an upper surface side of the partition wall and a lower piece arranged at a lower surface side of the partition wall, and
• the step of forming the air intake apparatus body includes a step of joining one of the upper piece and the lower piece, and the middle piece to each other by the vibration welding in a state where the jig-receiving portion is held by the jig, and thereafter further joining the other of the upper piece and the lower piece, and the middle piece to each other by the vibration welding in a state where the middle piece and the one of the upper piece and the lower piece is joined to each other and where the jig-receiving portion is held by the jig, the one of the upper piece and the lower piece including a relatively higher rigidity than the other and the other of the upper piece and the lower piece including a relatively lower rigidity than the one.