Patent Number: 047987006
Section: claims

1. In combination with a gas-cooled high temperature reactor having discrete absorber material elements for shutting down said reactor and a core filled with spherical fuel elements, a graphite side reflector comprising at least one nose-shaped projection protruding radially into the reactor core from said graphite side reflector,  said at least one nose-shaped projection comprising: (a) at least one vertically disposed cavity adapted to receive said discrete absorber material elements, (b) a vertically disposed, continuous opening which forms a passageway for communication between said cavity and the core of the reactor, and (c) blocking means cooperatively engaged with said projection and positioned within said continuous opening for preventing direct communication between said cavity and the core of the reactor,  said opening having a maximum width adjacent said cavity which is less than the minimum dimension of said discrete absorber elements in order to prevent passage of said elements into said continuous opening for said cavity. 2. The combination according to claim 1, wherein said blocking means comprises a graphite block cooperatively and freely engaged by correspondingly shaped portions of said projection and positioned transversely to said opening. 3. The combination according to claim 1, wherein said at least one nose-shaped projection comprises a plurality of graphite nose stones stacked one upon the other, said nose stones each including a vertically disposed continuous opening aligned with the vertically disposed continuous opening in adjacent nose stones. 4. The combination according to claim 1, comprising at least two nose-shaped projections uniformly positioned around the circumference of the reactor. 5. The combination according to claim 4, comprising four nose-shaped projections uniformly positioned around the circumference of the reactor in the form of opposing pairs aligned along a common axis. 6. The combination according to claim 1, wherein said vertically disposed , continuous opening extends from said cavity in said nose-shaped projection toward a center of said reactor core. 7. The combination according to claim 1, wherein said at least one nose-shaped projection comprises a plurality of grooves in the exterior surface thereof, wherein said continuous opening in the projection is a lateral extension of one of the exterior grooves toward said cavity. 8. The combination according to claim 1, wherein said continuous opening has a constant gap width. 9. The combination according to claim 1, wherein said continuous opening has a width which increases in dimension toward said core. 10. The combination according to claim 1, wherein said continuous opening has straight lateral surfaces. 11. The combination according to claim 1 wherein said continuous opening extends from said cavity in a direction away from the center portion of said core and comprises lateral curving surfaces.