LEAK INSPECTION DEVICE

PROBLEM TO BE SOLVED: To provide a leak inspection device that inspects leakage in a curved surface to be masked without increasing a pressing force of a masking rubber, while ensuring overall airtightness of a masking surface including a curved surface end part.SOLUTION: The surface of a masking rubber 3 to be pressed against a part 4 to be masked is a curved surface. A radius R2 of the curved surface of the masking rubber 3 is larger than a radius R3 of the curved surface of the part 4 to be masked. At both ends 7 of the masking rubber 3, thrust F can be efficiently applied.