Nuclear reactors

Claim 1

IN A NUCLEAR REACTOR INCLUDING A CORE PROVIDED WITH A PLURALITY OF CHANNELS AND A SHIELD SURRONDING SAID CORE, THE COMBINATION OF A FIRST PLUG EXTENDING THROUGH SAID SHIELD, GAS TIGHT MEANS FOR MOUNTING SAID PLUG ROTATABLY IN SAID SHIELD ABOUT A FIXED AXIS, SAID PLUG BEING PROVIDED WITH A CYLINDRICAL HOUSING, THE AXIS OF SAID HOUSING BEING AT AN ANGLE TO SAID FIXED AXIS AND INTERSECTING IT AT A POINT WHICH IS FIXED WITH RESPECT TO SAID SHIELD, SAID HOUSING EXTENDING FROM ONE SIDE OF SAID PLUG TO THE OTHER SIDE THEREOF, A SECOND PLUG MOUNTED WITH A GAS TIGHT FIT IN SAID FIRST PLUG SO AS TO BE ROTATABLE THEREIN ABOUT THE AXIS OF SAID HOUSING, SAID SECOND PLUG BEING PROVIDED WITH A CYLINDRICAL PASSAGE EXTENDING FROM ONE SIDE THEREOF TO THE OTHER SIDE, THE AXIS OF SAID PASSAGE BEING AT AN ANGLE TO THE AXIS OF SAID HOUSING AND INTERSECTING IT AT THE FIXED POINT WHERE THE AXIS OF SAID HOUSING INTERSECTS THE FIXED AXIS OF ROTATION OF THE FIRST PLUG, THE END FACE OF SAID CORE TURNED TOWARD SAID PLUG BEING FLAT, MEANS IN SAID END FACE FORMING INLETS FOR A PLURALITY OF SAID CHANNELS, RESPECTIVELY, SAID CHANNEL INLETS CONVERGING TOWARD SAID FIXED POINT, A STRAIGHT TUBE SLIDABLE WITH A GASTIGHT FIT ALONG ITS LONGITUDINAL AXIS IN SAID CYLINDRICAL PASSAGE, SAID TUBE EXTENDING ON BOTH SIDES OF SAID SECOND PLUG AND BEING OPEN AT BOTH ENDS, ONE END OF SAID TUBE BEING SHAPED AND DIMENSIONED TO FIT IN ANY OF SAID INLETS, AND MEANS CARRIED BY SAID SECOND PLUG FOR CAUSING SAID TUBE TO SLIDE IN SAID PASSAGE SO THAT IT CAN BE ENGAGED IN, OR REMOVED FROM, ANY OF SAID CHANNEL INLETS.