PURPOSE: To prevent vibration of protective tube due to fluid and enable stable measurement of temperature, by movably inserting a plurality of solid pieces in the air gap provided between the protective tube for thermocouple and the thermocouple inserted into the same protective tube.
CONSTITUTION: A thermocouple 1 is inserted into a protective tube for thermocuple 2, and an air gap H is provided between the thermocouple 1 and the protective tube 2. A plurality of solid pieces 3, which are cylindrical and have the outside diameter slightly smaller than the inside diameter of the protective tube 2, are inserted into the air gap H with the thermocouple 1 passed through in the central part thereof. When thus arranged thermocouple 1 and protective tube 2 are inserted into the fluid of which temperature is to be measured, the protective tube 2 may vibrate due to vortex, but the pieces 3 move within the air gap H to absorb the vibration energy, enlarging the damping at the end of the protective tube 2, so that the vibration may be prevented. Thus, the temperature may be meausred stably.
IKEGAMI YASUHIKO
ICHINOO HIROYUKI
