<；P>；PROBLEM TO BE SOLVED: To provide an air cell capable of detecting that the distance between the upper end of an air bag and a base member is smaller than a prescribed distance, reducing the manufacturing cost and improving the durability. <；P>；SOLUTION: If the air bag 11 is crushed and the upper end of the air bag 11 is brought into contact with an upper side part 14c, a thin film part 12c is deformed downward and the deformation is detected by a switch 15. Then, it can be detected that the distance between the upper end part 11c of the air bag 11 and the base member 12 is smaller than the prescribed distance. The switch 15 disposed outside of an air room AR can be easily connected to another device, which is advantageous in reducing the manufacturing cost. Furthermore, since it is not necessary to connect the lower end of an intermediate part 14b to the thin film part 12c, the thin film part 12c is not deformed even if the force in the horizontal direction is applied to the intermediate part 14b and the upper side part 14c, and the durability of the thin film part 12c can be secured. <；P>；COPYRIGHT: (C)2009,JPO&INPIT
