摘要 |
PURPOSE:To secure a structure dispensing with troublesome setting jobs as well as excellent in stability, by setting up a recess, sinking concavely downward from the upper side of a diaphragm balloon, on top of the balloon, while attaching a weight to the inside. CONSTITUTION:In order to keep constant the pressure of introgen gas to be sealed up inside an interspace between double shells of a cryostat double-shell tank, a diaphragm balloon type nitrogen gas holder is installed by means of interconnecting the interspace through. The top part of a diaphragm balloon 8 inside the holder is hollowed out into a circular shape and a flange 17 is solidly installed downward by connecting it to the edge, then a frame 18 is attached to the inside while a weight 11 is attached to the inside of the frame 18, thus the position of the center of gravity in the weight 11 comes below the top of the balloon so that the weight 11 is stabilized at the time of operation. |