Mitsubishi Jukogyo Kabushiki Kaisha

Hiroshi Yatabe

Shinichi Murakawa

Jinichi Miyaguchi

Yoshinori Takada

A system for monitoring an operating condition of a control rod drive mechanism (CRDM) having a pressure housing erectly mounted on a reactor vessel head closure, a vertically movable control rod drive shaft accommodated in the housing and an electromagnetically motive latch mechanism includes an accelerometer fitted to a housing upper end and signal recording means for receiving output signals from the accelerometer through signal processing means and recording the processed output signals. A system for monitoring and analyzing an operating condition of an electromagnetically driven CRDM having a lifting electromagnetic coil, a stationary gripper electromagnetic coil and a movable gripper electromagnetic coil includes a detector, fitted to the CRDM, for detecting vibrations caused by operation of the drive mechanism, a buffer amplifier for receiving current, and detection and control signals, a pre-processing unit for digitalizing these signals, and a processing unit for analytically processing both the current and detection signals.

Growing community of inventors

Kobe, Japan

Hiroshi Yatabe