Reel-type control rod drive and brake and braking mechanism

Claim 2

FOR USE IN A NUCLEAR REACTOR HAVING A VERTICALLY MOVABLE CONTROL ROD, A CABLE FOR SUSPENDING SAID ROD, A MOTOR, MEANS INCLUDING A CLUTCH FOR CONNECTING THE MOTOR TO SAID CABLE FOR ADJUSTING THE OPERATING HEIGHT OF THE ROD, AND MEANS FOR PROMPTLY DISENGAGING THE CLUTCH IN CASE OF AN EMERGENCY WHICH REQUIRES A QUICK FALL OF THE CONTROL ROD, THE METHOD OF CONTROLLING SAID EMERGENCY FALL OF THE CONTROL ROD TO PREVENT THE ROD FROM ARRIVING AT A DESIRED FINAL POSITION AT EXCESSIVE SPEED WHILE NOT UNDULY SLOWING DOWN THE FALL OF THE ROD TO A SAFE POSITION, WHICH METHOD COMPRISES, (A) FIRST DISENGAGING SAID CLUTCH SO AS TO PERMIT THE ROD TO FALL QUICKLY TO A SAFE POSITION (B) WHILE USING A PERCENTAGE OF THE ENERGY DEVELOPED IN SAID EMERGENCY FALL TO EFFECT UNI-DIRECTIONAL ROTARY MOVEMENT OF A FLYWHEEL GEARED TO AND DRIVEN BY SAID CABLE, (C) AND THEN, AFTER THE ROD REACHES A SAFE POSITION, PROGRESSIVELY INCREASING SAID PERCENTAGE AUTOMATICALLY DURING THE LATER PERIOD OF THE EMERGENCY FALL OF THE ROD, THEREBY PROGRESSIVELY DECELERATING THE FALL OF THE ROD DURING SAID FINAL PERIOD TO A SAFE SPEED BEFORE THE ROD REACHES ITS BOTTOM POSITION, AND (D) THEN DISCONNECTING SAID CABLE FROM SAID FLYWHEEL AND PERMITTING SAID FLYWHEEL TO CONTINUE ITS SAID UNI-DIRECTIONAL MOVEMENT.

Claim 3

FOR USE IN A NUCLEAR REACTOR HAVING A VERTICALLY MOVABLE CONTROL ROD, A CABLE FOR SUSPENDING SAID ROD, A MOTOR, AND MEANS CONNECTING THE MOTOR TO SAID CABLE FOR ADJUSTING THE HEIGHT OF THE ROD, MEANS FOR CONTROLLING THE FALL OF THE CONTROL ROD IN AN EMERGENCY WHICH REQUIRES A QUICK FALL OF THE ROD SO AS TO PREVENT THE ROD FROM ARRIVING AR A DESIRED LOWER POSITION AT EXCESSIVE SPEED WHILE NOT UNDULY PROLONGING THE EMERGENCY FALL OF THE ROD, WHICH MEANS COMPRISES, (A) A ROTATABLE SUPPORT FOR SAID CABLE INCLUDING A REEL FOR SUSPENDING SAID ROD DURING NORMAL OPERATION OF THE REACTOR, (B) A ROTATABLE FLYWHEEL, (C) MEANS FOR DRIVINGLY CONNECTING THE SUPPORT TO SAID FLYWHEEL SO AS TO ROTATE THE FLYWHEEL UNIDIRECTIONALLY THROUGHOUT THE DESCENT OF THE ROD, INCLUDING A FREE-WHEELING CLUTCH PERMITTING SAID WHEEL TO CONTINUE ITS SAID ROTATION FREE FROM THE CABLE AFTER SAID ROD REACHES ITS BOTTOM POSITION IN THE REACTOR, (D) A CLUTCH FOR DISENGAGING SAID MOTOR FROM SAID CABLE AT THE START OF THE EMERGENCY FALL, (E) AND INCLUDING MEANS, OPERATING SUBSEQUENT TO THE ARRIVAL OF THE ROD AT A SAFE POSITION, FOR PROGRESSIVELY TRANSFERRING FROM THE ROD TO THE WHEEL A SUFFICIENT AMOUNT OF THE KINETIC ENERGY ACQUIRED BY THE ROD IN ITS FALL TO PROGRESSIVELY DECELERATE THE FALL OF THE ROD TO A SAFE SPEED BEFORE THE ROD REACHES ITS BOTTOM POSITION.

Claim 4

FOR USE IN A NUCLEAR REACTOR HAVING A VERTICALLY MOVABLE CONTROL ROD, A CABLE FOR SUSPENDING SAID ROD, A MOTOR, AND MEANS CONNECTING THE MOTOR TO SAID CABLE FOR ADJUSTING THE HEIGHT OF THE ROD, MEANS FOR CONTROLLING THE FALL OF THE CONTROL ROD IN AN EMERGENCY WHICH REQUIRES A QUICK FALL OF THE ROD SO AS TO PREVENT THE ROD FROM ARRIVING AR A DESIRED LOWER POSITION AT EXCESSIVE SPEED WHILE NOT UNDULY PROLONGING THE EMERGENCY FALL OF THE ROD, WHICH MEANS COMPRISES, (A) A ROTATABLE SUPPORT FOR SAID CABLE INCLUDING A REEL FOR SUSPENDING SAID ROD DURING NORMAL OPERATION OF THE REACTOR, (B) A ROTATABLE FLYWHEEL, (C) MEANS FOR DRIVINGLY CONNECTING THE SUPPORT TO SAID FLYWHEEL SO AS TO ROTATE THE FLYWHEEL UNIDIRECTIONALLY THROUGHOUT THE DESCENT OF THE ROD, INCLUDING A FREE-WHEELING CLUTCH PERMITTING SAID WHEEL TO CONTINUE ITS SAID ROTATION FREE FROM THE CABLE AFTER SAID ROD REACHES ITS BOTTOM POSITION IN THE REACTOR, (D) A CLUTCH FOR DISENGAGING SAID MOTOR FROM SAID CABLE AT THE START OF THE EMERGENCY FALL, (E) AND INCLUDING MEANS, OPERATING SUBSEQUENT TO THE ARRIVAL OF THE ROD AT A SAFE POSITION, FOR PROGRESSIVELY TRANSFERRING FROM THE ROD TO THE WHEEL A SUFFICIENT AMOUNT OF THE KINETIC ENERGY ACQUIRED BY THE ROD IN ITS FALL TO PROGRESSIVELY DECELERATE THE FALL OF THE ROD TO A SAFE SPEED BEFORE THE ROD REACHES ITS BOTTOM POSITION.