Bonded body

A bonded body, comprising:

• a first member;
• and
• a second member performing a vibration welding with the first member so as to form the bonded body, wherein
• the first member includes
• a first base portion extending along an edge on the second member side of the first member, and
• a first welded portion protruding from the first base portion toward a second member side,
• the second member includes
• a second base portion extending along an edge on the first member side of the second member and disposed to face the first base portion, and
• a second welded portion protruding from the second base portion toward a first member side and having a distal end which is vibration welded to the tip of the first welded portion,
• a width of the first welded portion is larger than a width of the second welded portion,
• in a first region of the portion where the first member and the second member are joined, a first rib formed on the first member so as to protrude from the first base portion toward the second member side at a position separated from the first welded portion, covers the first welded portion and the second welded portion from the side,
• in a second region different from the first region, in the portion where the first member and the second member are joined, a second rib formed on the second member so as to protrude from the second base portion toward the first member side at a position separated from the second welded portion, covers the first welded portion and the second welded portion from the side, and
• in a connection region connecting the first region and the second region in a portion where the first member and the second member are joined,
• the first rib and the second rib are formed so that the amount of protrusion of the first rib gradually decreases and the amount of protrusion of the second rib gradually increases from the first region side to the second region side.