PACKING

PROBLEM TO BE SOLVED: To follow the vertical movement of a lid main body to deform elastically so as to improve sealability of the lid main body and a frame body by forming a packing main body into a shape which is long longitudinally and forming a cavity in the inside thereof. SOLUTION: A packing main body 10 is constituted in such a manner that a pair of adhesion parts 14, 14' which protrude upward are connected in an upper end part 14a thereof and are integrated and that a cavity part 12 which is long longitudinally and has an elliptical shape is formed between the adhesion parts 14 and 14'. Furthermore, the pair of adhesion parts 14, 14' are formed in such a manner that their wall thickness is gradually reduced toward the upper end part 14a. Moreover, the adhesion parts 14, 14' protrude in the vertical direction in such a manner that they are sufficiently longer than a clearance between a packing seat 9 of a lid main body 3 and a lower face 2b of a frame body 2 which is caused when the lid main body 3 is fitted in the frame body 2. The packing main body 10 is formed by a material which can be deformed elastically and adheres to the packing seat 9 to prevent the passing of fluid.