Control device for a nuclear reactor

Claim 1

CONTROL DEVICE FOR A NUCLEAR REACTOR, COMPRISING A REACTOR CORE HOUSING, A SUBSTANTIALLY MOVABLE NEUTRON ABSORBING MEANS INSERTABLE INTO SAID REACTOR CORE HOUSING, SAID CONTROL MEANS HAVING A HEAD MEMBER AND A NEUTRON ABSORBNG MEMBER AND A TUBE MEMBER JOINING SAID HEAD MEMBER AND SAID NEUTRON ABSORBING MEMBER, A CLOSED SECOND HOUSING HAVING AN UPPER AND A LOWER WALL AND AT LEAST ONE SIDE WALL, SAID SECOND HOUSING ENCLOSING SAID HEAD MEMBER, A SUBSTANTIALLY VERTICALLY MOVABLE AND MECHANICALLY DRIVEN MEMBER WITHIN SAID SECOND HOUSING, SAID SECOND HOUSING HAVING IN ITS LOWER WALL PRESSURE SEALING MEANS SEALING AGAINST SAID TUBE MEMBER, THEREBY SEALING SAID REACTOR CORE HOUSING FROM SAID SECOND HOUSING, SAID MECHANICALLY DRIVEN MEMBER BEING LOCATED ABOVE SAID HEAD MEMBER, SAID MECHANICALLY DRIVEN MEMBER AND SAID HEAD MEMBER HAVING RESPECTIVELY FIRST AND SECOND SEAT SURFACES MATCHING EACH OTHER TO FORM A TIGHT SEAL WHEN PRESSED TOGETHER, SAID SEAL DEFINING A LOW PRESSURE SPACE INSIDE SAID SEAT SURFACES, SAID TUBE MEMBER CONNECTING SAID LOW PRESSURE SPACE TO THE INTERIOR OF SAID REACTOR CORE HOUSING, SAID HEAD MEMBER HAVING AN EFFECTIVE PRESSURE BEARING AREA, SAID DEVICE FURTHER COMPRISING MEANS FOR FEEDING A PRESSURE MEDIUM TO SAID SECOND HOUSING OUTSIDE SAID SEAT SURFACES TO EXERT A PRESSURE HIGHER THAN THE PRESSURE IN SAID LOW PRESSURE SPACE ON SAID PRESSURE BEARING AREA, SAID HIGHER PRESSURE BEING HIGH ENOUGH TO PRESS SAID HEAD MEMBER INTO ABUTTING ENGAGEMENT WITH SAID MECHANICALLY DRIVEN MEMBER, AND MEANS FOR RELIEVING SAID HIGHER PRESSURE TO ALLOW SAID HEAD MEMBER TO MOVE DOWNWARDS BY ACTION OF GRAVITY, SAID HEAD MEMBER BEING SPACED FROM SAID SIDE WALL OF SAID SECOND HOUSING TO PROVIDE A PRESSURE MEDIUM CONTAINING SPACE FORMING AT LEAST ONE FLOW PASSAGE FOR PRESSURE MEDIUM DISPLACED BY SAID MEMBER DURING SAID GRAVITY INDUCED DOWNWARDS MOVEMENT OF SAID HEAD MEMBER.