Apparatus for detecting amount of liquid nitrogen

摘要

An apparatus for detecting an amount of liquid nitrogen, has a table for supporting a Dewar vessel in which liquid nitrogen used for cooling a semiconductor radio detector is contained. A motion conversion mechanism is engaged with the table for converting the movement of the table in the up and down direction in response to changes in the weight of the liquid nitrogen in the vessel and amplifying and movement. The motion conversion mechanism includes a disk rotated by the amplified motion of the table, and a plurality of sensors adjacent the disk for detecting the rotational position of the disk which is representative of the weight of the liquid nitrogen in the vessel.