Patent ID: 8852704

Claim:
A resin welded body in which a first resin part and a second resin part are placed opposite to each other with a predetermined clearance therebetween and form a closed space therebetween, at least part of abutting surfaces of the first and second resin parts being joined by welding, the resin welded body comprising, when a X-Y plane is a plane parallel to the abutting surfaces and a Z direction is a direction perpendicular to the X-Y plane: a first protrusion in a circumferential shape that is provided on any one of the first and second resin parts and that protrudes in the Z direction in the closed space; a second protrusion in a circumferential shape that is provided on the resin part opposite to the resin part on which the first protrusion is provided and that protrudes in the Z direction on the outer circumference side with respect to the first protrusion; a third protrusion that is provided on any one of the first and second resin parts and that protrudes in the Z direction on the outer circumference side with respect to the second protrusion and abuts the opposite resin part to define the clearance between the first and second resin parts; and a ring-shaped sealing member that is held between the outer circumference side of the first protrusion and the inner circumference side of the second protrusion and that is pressed in a direction parallel to the X-Y plane.